[House Hearing, 110 Congress]
[From the U.S. Government Publishing Office]
BRIDGE SAFETY: NEXT STEPS
TO PROTECT THE NATION'S
CRITICAL INFRASTRUCTURE
=======================================================================
HEARING
BEFORE THE
COMMITTEE ON SCIENCE AND TECHNOLOGY
HOUSE OF REPRESENTATIVES
ONE HUNDRED TENTH CONGRESS
FIRST SESSION
__________
SEPTEMBER 19, 2007
__________
Serial No. 110-53
__________
Printed for the use of the Committee on Science and Technology
Available via the World Wide Web: http://www.house.gov/science
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______
COMMITTEE ON SCIENCE AND TECHNOLOGY
HON. BART GORDON, Tennessee, Chairman
JERRY F. COSTELLO, Illinois RALPH M. HALL, Texas
EDDIE BERNICE JOHNSON, Texas F. JAMES SENSENBRENNER JR.,
LYNN C. WOOLSEY, California Wisconsin
MARK UDALL, Colorado LAMAR S. SMITH, Texas
DAVID WU, Oregon DANA ROHRABACHER, California
BRIAN BAIRD, Washington ROSCOE G. BARTLETT, Maryland
BRAD MILLER, North Carolina VERNON J. EHLERS, Michigan
DANIEL LIPINSKI, Illinois FRANK D. LUCAS, Oklahoma
NICK LAMPSON, Texas JUDY BIGGERT, Illinois
GABRIELLE GIFFORDS, Arizona W. TODD AKIN, Missouri
JERRY MCNERNEY, California JO BONNER, Alabama
LAURA RICHARDSON, California TOM FEENEY, Florida
PAUL KANJORSKI, Pennsylvania RANDY NEUGEBAUER, Texas
DARLENE HOOLEY, Oregon BOB INGLIS, South Carolina
STEVEN R. ROTHMAN, New Jersey DAVID G. REICHERT, Washington
JIM MATHESON, Utah MICHAEL T. MCCAUL, Texas
MIKE ROSS, Arkansas MARIO DIAZ-BALART, Florida
BEN CHANDLER, Kentucky PHIL GINGREY, Georgia
RUSS CARNAHAN, Missouri BRIAN P. BILBRAY, California
CHARLIE MELANCON, Louisiana ADRIAN SMITH, Nebraska
BARON P. HILL, Indiana PAUL C. BROUN, Georgia
HARRY E. MITCHELL, Arizona
CHARLES A. WILSON, Ohio
C O N T E N T S
September 19, 2007
Page
Witness List..................................................... 2
Hearing Charter.................................................. 3
Opening Statements
Statement by Representative Bart Gordon, Chairman, Committee on
Science and Technology, U.S. House of Representatives.......... 7
Written Statement............................................ 7
Statement by Representative Ralph M. Hall, Minority Ranking
Member, Committee on Science and Technology, U.S. House of
Representatives................................................ 8
Written Statement............................................ 9
Statement by Representative David Wu, Chairman, Subcommittee on
Technology and Innovation, Committee on Science and Technology,
U.S. House of Representatives.................................. 10
Written Statement............................................ 11
Statement by Representative Phil Gingrey, Minority Ranking
Member, Subcommittee on Technology and Innovation, Committee on
Science and Technology, U.S. House of Representatives.......... 11
Written Statement............................................ 13
Prepared Statement by Representative Jerry F. Costello, Member,
Committee on Science and Technology, U.S. House of
Representatives................................................ 13
Prepared Statement by Representative Russ Carnahan, Member,
Committee on Science and Technology, U.S. House of
Representatives................................................ 14
Prepared Statement by Representative Charlie Melancon, Member,
Committee on Science and Technology, U.S. House of
Representatives................................................ 14
Prepared Statement by Representative Harry E. Mitchell, Member,
Committee on Science and Technology, U.S. House of
Representatives................................................ 15
Witnesses:
Mr. Dennis C. Judycki, Associate Administrator, Research,
Development, and Technology, Federal Highway Administration,
U.S. Department of Transportation; Accompanied by Mr. Benjamin
Tang, Principal Bridge Engineer/Team Leader, Office of Bridge
Technology, Federal Highway Administration, U.S. Department of
Transportation
Oral Statement............................................... 16
Written Statement............................................ 17
Biography for Dennis C. Judycki.............................. 23
Biography for Benjamin Tang.................................. 24
Mr. Harry Lee James, Deputy Executive Director and Chief
Engineer, Mississippi Department of Transportation; Member,
Standing Committee on Highways, American Association of State
Highway and Transportation Officials
Oral Statement............................................... 25
Written Statement............................................ 26
Biography.................................................... 37
Dr. Kevin C. Womack, Director, Utah Transportation Center;
Professor of Civil and Environmental Engineering, Utah State
University
Oral Statement............................................... 38
Written Statement............................................ 39
Biography.................................................... 46
Mr. Mark E. Bernhardt, Director, Facility Inspection, Burgess &
Niple, Inc.
Oral Statement............................................... 46
Written Statement............................................ 48
Biography.................................................... 50
Discussion....................................................... 54
Appendix 1: Answers to Post-Hearing Questions
Mr. Dennis C. Judycki, Associate Administrator, Research,
Development, and Technology, Federal Highway Administration,
U.S. Department of Transportation.............................. 70
Mr. Harry Lee James, Deputy Executive Director and Chief
Engineer, Mississippi Department of Transportation; Member,
Standing Committee on Highways, American Association of State
Highway and Transportation Officials........................... 76
Dr. Kevin C. Womack, Director, Utah Transportation Center;
Professor of Civil and Environmental Engineering, Utah State
University..................................................... 78
Mr. Mark E. Bernhardt, Director, Facility Inspection, Burgess &
Niple, Inc..................................................... 82
Appendix 2: Additional Material for the Record
Statement of Christopher C. Higgins, Oregon State University
College of Engineering......................................... 86
Statement of Michael Todd, Associate Professor of Structural
Engineering, University of California-San Diego, and Charles
Farrar, Leader, The Engineering Institute, Los Alamos National
Laboratory..................................................... 88
Statement of Larry W. Frevert, President, American Public Works
Association.................................................... 95
BRIDGE SAFETY: NEXT STEPS TO PROTECT THE NATION'S CRITICAL
INFRASTRUCTURE
----------
WEDNESDAY, SEPTEMBER 19, 2007
House of Representatives,
Committee on Science and Technology,
Washington, DC.
The Committee met, pursuant to call, at 10:05 a.m., in Room
2318 of the Rayburn House Office Building, Hon. Bart Gordon
[Chairman of the Committee] presiding.
hearing charter
COMMITTEE ON SCIENCE AND TECHNOLOGY
U.S. HOUSE OF REPRESENTATIVES
Bridge Safety: Next Steps
to Protect the Nation's
Critical Infrastructure
wednesday, september 19, 2007
10:00 a.m.-12:00 p.m.
2318 rayburn house office building
I. Purpose
On Wednesday, September 19, 2007, the Committee on Science and
Technology will hold a hearing entitled ``Bridge Safety: Next Steps to
Protect the Nation's Critical Infrastructure'' to examine research and
development activities to improve the safety of the Nation's bridges.
The hearing will explore the current state of bridge-related research,
including government and academic research into materials, design
elements, and testing and inspection technologies. Witnesses will also
discuss future research priorities for building improved bridge
infrastructure and maintaining current bridges to avoid catastrophic
failure.
II. Witnesses
Mr. Dennis Judycki is the Associate Administrator for Research,
Development, and Technology at the Federal Highway Administration
(FHWA) of the U.S. Department of Transportation (U.S. DOT) and Director
of U.S. DOT's Turner-Fairbank Highway Research Center (TFHRC).
Mr. Benjamin Tang is a Principal Bridge Engineer for the Office of
Bridge Technology at the Federal Highway Administration of the U.S.
DOT.
Dr. Kevin Womack is the Director of the Utah Transportation Center and
Professor of Civil and Environmental Engineering at Utah State
University.
Mr. Harry Lee James is the Deputy Executive Director and Chief Engineer
for the Mississippi Department of Transportation.
Mr. Mark Bernhardt is the Director of Facility Inspection for Burgess &
Niple, an engineering firm.
III. Brief Overview
Structural problems, both major and minor, plague a
significant portion of bridges in the United States. According
to the U.S. Department of Transportation's National Bridge
Inventory, 73,764 bridges around the U.S. (12.4 percent of all
bridges) were classified as ``structurally deficient'' in 2006,
including the bridge that collapsed in Minnesota. The American
Society of Civil Engineers (ASCE) in 2005 gave the Nation's
bridge infrastructure a ``C'' grade in its Report Card for
America's Infrastructure because of the large number of
deficient bridges. However, the definition of structural
deficiency is broad, and can cover everything from non-
structural paving issues to serious flaws. State and local
inspectors are responsible for determining which bridges need
the most immediate attention.
The challenge for policy-makers at the State, local,
and federal level is to determine which bridges are the highest
priority for repairs given limited funding. ASCE estimates that
repairing every deficient bridge across the Nation would cost
$9.4 billion per year for 20 years. Inspectors use a variety of
methods to determine if a bridge has immediate need of repair,
including visual inspection, sensors, and other non-destructive
testing technologies. The existing methods are imperfect,
however, and additional research is needed to develop methods
that will provide better quality data on which bridges are in
greatest need of immediate repair.
The Federal Highway Administration, State highway
administrations, and universities are sponsoring and carrying
out research to improve bridge design, maintenance, and
inspections. Current research covers a variety of fields,
including materials, engineering design, technology
development, and modeling. However, transferring successful
technologies to end-users such as state highway administration
officials is challenging because of cost concerns and training
issues for advanced technology.
Additional research is needed to better understand
the current and future demands on bridges. Traffic loads are
significantly higher than when many of the country's bridges
were built, especially from truck traffic. FHWA is supporting
research to design the ``Bridge of the Future'' with the goal
of a century-long lifespan. This and similar projects should
include projections for bridge usage throughout the intended
lifespan to ensure that the bridge meets users' needs.
IV. Issues and Concerns
How are bridges currently tested for safety, and how effective are
current testing methods and technologies? What technologies and
techniques currently exist to improve bridges' structural integrity?
States are currently responsible for all bridge inspections, which must
be carried out biennially under the National Bridge Inspection
Standards (NBIS), which are enforced by FHWA. If a bridge is deemed
potentially problematic, inspectors can increase the frequency of
evaluations. Approximately twelve percent of bridges are inspected
annually. Inspectors examine the bridge deck (primary travel surface),
superstructure (which supports the deck), and substructure (which
supports the superstructure). Each component is given a rating based on
its current condition, ranging from excellent to failed or out of
service. If the bridge gets less than 50 points in its overall rating,
it can be classified as structurally deficient. For reference, before
it collapsed, the I-35W bridge in Minneapolis received a score of 50.
Some technology is currently in use to aid inspectors in their
assessments of bridges, but generally bridge inspectors depend on
visual observations to determine if a bridge is deficient in any
category. Bridge inspectors are trained through university programs and
also must complete required courses through FHWA's National Highway
Institute (NHI). These courses are also used to deliver information
about new technologies emerging from the U.S. DOT.
What future research is needed in the overall field of bridge safety,
and how can engineers insure that new technologies are an improvement
on the current state-of-the-art? Current bridge research covers three
general fields: structural engineering, materials, and inspection
technologies. Within these research areas, many different projects are
carried out or funded by universities, State departments of
transportation, and the Federal Government. Some private research,
especially in the area of technology design and development, is also
carried out by industry. Research priorities are generally guided by
end-user needs, and the transportation research community has a strong,
centralized structure for sharing both research results and technology
needs. The Transportation Research Board (TRB), part of the National
Research Council (NRC), hosts an annual meeting and other smaller
events to facilitate collaboration among researchers and end users that
is a primary source of information on research priorities. Following
the bridge collapse in Minnesota, TRB put a greater focus on the
specific field of bridge safety and announced that its 2008 annual
meeting would highlight the issue of aging infrastructure. AASHTO also
convenes a bridge committee comprised of State highway officials who
are able to discuss needs specific to their states.
FHWA is also working on their Bridge of the Future project, which
aims to use innovative designs and materials to build a bridge that
will have a lifespan of at least a century (compared to current 25- to
50-year lifespans). However, the new designs, materials, and
technologies that are developed through these research projects will
only be useful if they are able to meet the long-term needs of users.
Many current bridges--81,257 in 2007--are functionally obsolete because
engineers were unable to accurately predict the types of traffic loads
throughout the bridge's intended lifespan.
How can non-destructive testing of existing bridges and lessons from
the Minnesota collapse be used to determine which bridges are the most
susceptible to catastrophic failure? Currently, bridge inspectors rely
primarily on visual inspections to determine whether bridges are in
need of repair. While these inspectors go through rigorous training and
take regular refresher courses to keep their skills up to date, there
are obvious limits to inspections which cover only surface features of
the bridges. New technologies are being introduced to help inspectors
see into the structural elements of bridges so that they may better
determine the overall strength and integrity. But there are barriers to
adoption of these new technologies. Many are expensive and well outside
the budget of state highway administrations. Others take highly
technical training to operate effectively and are too difficult for
busy bridge inspectors to learn to use. Some technologies also require
near continuous monitoring or modeling to identify potential problems.
Additional research is needed to develop technologies for non-
destructive testing of bridges that are effective and efficient for
bridge inspectors so that catastrophic failures can be predicted before
they happen.
What technology transfer programs exist at FHWA and university
transportation research centers, and how effective are those programs?
In transportation fields, technology transfer is a special challenge
because no solution works well for everyone. Differences in traffic
loads, climate, size and shape, and other bridge characteristics mean
that new engineering designs, materials, and technologies may work well
for a bridge engineer in California but not in New York or Florida.
Thus, technology transfer efforts must include both determining the
customer's unique needs and transferring the appropriate technology.
For the former, FHWA and the University Transportation Centers depend
on organizations of end-users, including TRB and AASHTO, to facilitate
discussions of technology needs. The strong participation in these
groups means that end-users are making their needs known to the
appropriate people, but technology adoption remains slow. FHWA programs
to encourage the adoption of new technology include seminars and
discussions at TRB events and courses offered at the National Highway
Institute (NHI) to train engineers and inspectors in the use of new
technology.
V. Background
The collapse of the I-35W bridge in Minnesota was, unfortunately,
not the first of its kind. In 1967, a bridge from West Virginia to Ohio
collapsed, killing dozens of people and spurring the Federal Highway
Administration to standardize inspections of bridges to avoid future
tragedies. The National Bridge Inspection System now uses a point
system to help state inspectors and the Federal Government determine
which bridges are in greatest need of repair. On a 100 point scale,
bridges that score less than 50 points are described as ``structurally
deficient.'' Some bridges are also classified as ``functionally
obsolete'' meaning that they are unable to perform to the current
necessary traffic capacity. These bridges limit the size of vehicles
allowed to cross. Neither designation means that the bridge is in
imminent danger of collapse. Points are awarded based on the condition
of the substructure, superstructure, and surface; thus, a low scoring
bridge may merely need repaving to bring it back from structural
deficiency.
The sheer number of structurally deficient bridges around the
country is cause for concern, though, because many do have underlying
structural problems. In 2006, FHWA found that 73,764 bridges were
structurally deficient, including the one that collapsed in Minnesota.
There is not a centralized system that the Federal Government uses to
further classify structurally deficient bridges as suffering from
dangerous structural (as opposed to cosmetic or less urgent)
conditions. This makes it far more difficult to determine the true
vulnerability of the bridges in the United States. The American Society
of Civil Engineers (ASCE) has carried out their own assessment of the
Nation's bridges, and found that the Nation's urban bridges, which
carry much larger than average numbers of vehicles daily, are
classified as structurally deficient at a much higher percentage than
rural bridges, making the situation more dangerous than the number
suggest on their own. ASCE has called for stronger investment in
repairing infrastructure and long-term research efforts. Repairs,
however, are an enormous financial challenge. ASCE anticipates a total
cost of $188 billion to repair all current structurally deficient
bridges around the country.
While the issue of bridge structural problems is not new, changing
patterns in the U.S. transportation sector have made fixing deficient
bridges much more pressing. The Bureau of Transportation Statistics
(BTS) found that the number of vehicles on roads and bridges has
increased from 156 million to 235 million since 1980, and economic
growth has spurred the long haul trucking industry to put more and
heavier trucks on the road. These traffic loads are far higher than
those originally anticipated by bridges' engineers, and may accelerate
deterioration of already crumbling infrastructure.
Because it is financially and logistically unfeasible to repair all
problematic bridges around the country in the short-term, State highway
administrations, bridge inspectors, and the public rely on the results
of research and technology development to avoid catastrophic and deadly
collapses. The research community has recognized bridges as a priority,
and is putting available resources into both short- and long-term
research to improve safety. However, funding for this research is
extremely limited. FHWA has only approximately $22 million available
for bridge related research, and must leverage research carried out by
universities, states, and private industry to move forward.
Chairman Gordon. I want to welcome everyone to today's
hearing on Bridge Safety: Next Steps to Protect the Nation's
Critical Infrastructure. We were all horrified by the images of
I-35W bridge collapse in Minneapolis last month, and the
Congress has begun moving to address the serious problem of
deteriorating bridges.
Infrastructure in the United States, and in my own home
State of Tennessee, 37 bridges were found to be deficient by
Road Improvement Survey in 2005, and I am sure that my
colleagues on the Committee could all share similar statistics.
Clearly the disaster that struck Minnesota could have happened
anywhere. This is a wakeup call that we need to be doing more
to strengthen and secure our bridges now and for the long-term.
And while funding bridges is important and necessary, we cannot
keep on with business as usual if we are to maintain a safe,
national inventory of nearly 600,000 bridges. In the American
Society of Civil Engineers' 2005 Infrastructure Report card,
they reported that it would cost upwards to $188 billion just
to fix the Nation's current structurally deficient bridges.
There has to be a better, more efficient way. I am hoping our
witnesses today can shed some light on what that better way is.
The witnesses here today represent the Federal Government,
State government, academia, and industry. Each of these groups
is working hard on the innovative research and development that
will hopefully help us to prevent these types of tragedies in
the future. They are developing new materials for stronger
decks, new engineering techniques for more resilient bridges,
new technologies to help inspectors more accurately assess the
conditions of a bridge, and of course, new technologies are
only useful insofar as they are adopted by builders and
inspectors. So, I hope to hear more about technological
transfer programs and what we can do to make innovative
technology more accessible to hardworking engineers and to
inspectors that need them.
Investing our resources wisely is the first step to
ensuring the American public crosses the Nation's bridges
confidently.
Before I recognize my friend and colleague, Ranking Member,
Mr. Hall, let me say that we are going to allow both--have two
additional opening statements by our Chairman and Ranking
Member of the Subcommittee on Technology Innovation which
covers this area, I am going to have to briefly step across the
hall. I have a bill concerning 9-1-1 that is important for all
of us, and so I am going to turn to Mr. Wu and recognize Mr.
Hall for his opening statement.
[The prepared statement of Chairman Gordon follows:]
Prepared Statement of Chairman Bart Gordon
I want to welcome everyone to today's hearing on Bridge Safety:
Next Steps to Protect the Nation's Critical Infrastructure. We were all
horrified by the images of the I-35W bridge collapse in Minneapolis
last month, and Congress has begun moving to address the serious
problems of deteriorating bridge infrastructure in the United States.
In my home State of Tennessee, 37 bridges were found to be deficient by
a Road Improvement Survey in 2005. My colleagues on the Committee could
all share similar statistics. Clearly, the disaster that struck
Minnesota could have happened anywhere. This is a wakeup call that we
need to be doing more to strengthen and secure our bridges now and for
the long-term.
While funding repairs is important and necessary, we cannot keep on
with business as usual if we are to maintain a safe national inventory
of nearly 600,000 bridges. In the American Society of Civil Engineers'
2005 Infrastructure Report Card, they reported that it would cost
upwards of $188 billion just to fix our nation's current structurally
deficient bridges. There has to be a better, more efficient way. I'm
hoping our witnesses today can shed some light on what that better way
is.
The witnesses here today represent the Federal Government, State
government, academia and industry. Each of these groups is working hard
on the innovative research and development that will hopefully help us
prevent these types of tragedies in the future. They are developing new
materials for stronger decks, new engineering techniques for more
resilient bridges, new technologies to help inspectors more accurately
assess the condition of a bridge. Of course, new technologies are only
useful insofar as they are adopted by builders and inspectors. I hope
to hear more about technology transfer programs, and what we can all do
to make innovative technologies more accessible to the hardworking
engineers and inspectors that need them.
Investing our resources wisely is the first step to ensuring that
the American public crosses the Nation's bridges confidently.
I'd now like to recognize my colleague, the Ranking Member from
Texas, Mr. Hall, for an opening statement. We'll then allow two
additional opening statements from the Chairman and Ranking Member of
the Subcommittee on Technology and Innovation, which covers surface
transportation R&D for the Committee.
Mr. Hall. I thank you, Mr. Chairman, and I say good morning
to you gentlemen. Thank you for the time you are giving us
today, the time you have given us in preparation and your trip
home. We appreciate you being here because your input is what
we really look to in order to write our legislation because you
know more about what we are talking about than we do, and you
are very kind and gracious to give us your time.
We are a nation of infrastructure. It is kind of funny. I
have had a lot of advice from a lot of people about these
bridges and everything. Every time I get up on one when I look
way down there and see little people in small cars I have some
kind of an eerie feeling, you know, thinking that some day that
the thing is going to fall if we don't do something about it
and don't keep checking it. One guy suggested to me that--my
district goes several hundred miles from Dallas County to the
end of Texarkana, Bowie County, over to the Arkansas border,
about 300 miles. He said, if you can stay on them farm-to-
market roads, you will be a lot safer. I don't know if that is
true or not, but maybe you folks are going to be able to help
us.
More than any other country in the world, we do rely on a
massive, interconnected web of power lines and power plants,
telecommunications facilities, train tracks, roadways, and
bridges to, you know, go about our everyday lives; and that is
why tragedies like the I-35 bridge collapse in Minneapolis
strike each of us so personally. During our own, everyday lives
since August the 1st we have all thought of the 185 people on
the I-35 bridge when it collapsed and the 13 who perished.
Perhaps as we drive across bridges in our hometowns on the way
to work or to the school or to the shopping center down the
road we think about it, and it causes concern. Clearly the loss
of life is unacceptable, and then what to do about it, what we
can do about it, and how practical it is to do what we ought to
do about it and whether or not we will do what we ought to do
is something that we just have to work out together. And we
have to listen to you and try to adapt our ability to respond
to what your recommendations are.
Ensuring the safety of our basic infrastructure has to be
the top priority of Federal, State, and local governments. This
is a core principle of public policy and the reason the
Committee is meeting here today. Sadly, this is not the first
time that a major bridge has failed. In 1967, 46 people died
from the collapse of the Silver Bridge in Point Pleasant, West
Virginia. The following year, the Federal Government began a
nationwide bridge inspection program. Today the National Bridge
Inventory including almost 600,000 bridges, almost 25 percent
of these are over 50 years old. Of the 49,518 bridges on the
inventory in my home State of Texas, 2,219 or five percent are
considered structurally deficient. I live in the smallest
county in Texas. There are 254 counties. Mine is the smallest
geographically. I have bridges that I am very fearful of,
bridges that I have pictures of my wife and me standing,
leaning up against the banister the day they were poured; and
that is 50 or 60 years ago. Those bridges are probably very
dangerous. This designation of structurally deficient doesn't
mean that these bridges are in immediate danger of collapse; it
does, however, mean that signs of fatigue and stress are
beginning to show and that the bridge requires close
monitoring. The I-35 bridge was one such structurally deficient
bridge, however, and was inspected a year prior to the
collapse.
So today we have a panel before us who can tell us what we
are doing as a nation to improve the monitoring and inspection
of bridges. What are the technologies and the skills that will
allow us to better assess and monitor the health of these
critical pieces of infrastructure? What can be done in the next
five or 10 years to improve the data we have on bridges and our
ability to correct interpret that data? And can we do this
while also attending to the other challenges facing
transportation officials such as growing congestion and
deteriorating roadways?
I don't know. We would like to hear that from you all. I
wrote a bill about the drought that we have and how to address
it later and how to have quicker response for the ranchers and
farmers before it is too late; and of course, you know what the
first question was when I was back in my district, telling them
about how I had offered the drought bill. And one old farmer
said, well, Congressman, can you make it rain? And I had just
admitted that I couldn't and we would do something about that
at a later time. And sure enough we had too damn much rain
about three weeks ago and Texoma Lake overran and drowned out
the rice farmers down below. Now if I go back to that same
place and make that speech, he will say, Congressman, can you
make it stop raining? So we can only do what you guys and
ladies and gentlemen point out to us and help us give your best
judgment on it. We appreciate your being here.
Mr. Chairman, I yield back.
[The prepared statement of Mr. Hall follows:]
Prepared Statement of Representative Ralph M. Hall
Good morning Mr. Chairman.
We are a nation of infrastructure. More than any other country in
the world we rely on a massive, interconnected web of power lines and
power plants, telecommunications facilities, and train tracks,
roadways, and bridges to go about our everyday lives.
This is why tragedies like the I-35 bridge collapse in Minneapolis
strike each of us so personally. During our own everyday lives since
August 1st we have all thought of the 185 people on the I-35 bridge
when it collapsed and the thirteen who perished, perhaps as we drove
across bridges in our home towns on the way to work, or to school, or
to the shopping center down the road.
Clearly this loss of life is unacceptable.
Ensuring the safety of our basic infrastructure must be the top
priority of our Federal, State, and local governments. This is a core
principle of public service and the reason this committee is meeting
today.
Sadly, this is not the first time that a major bridge has failed.
In 1967, forty-six people died from the collapse of the Silver Bridge
in Point Pleasant, West Virginia. The following year the Federal
Government began a nationwide bridge inspection program. Today, the
National Bridge Inventory, includes almost 600,000 bridges. Almost
twenty-five percent of those are over fifty years old. Of the 49,518
bridges on the inventory in my home State of Texas, 2,219 or five
percent are considered ``structurally deficient.''
This designation, ``structurally deficient,'' does not mean these
bridges are in immediate danger of collapsing. It does, however, mean
that signs of fatigue and stress are beginning to show and that the
bridge requires close monitoring. The I-35 bridge was one such
``structurally deficient'' bridge, however, and was inspected a year
prior to the collapse.
So, today, we have a panel before us who can tell us what we're
doing as a nation to improve the monitoring and inspections of bridges.
What are the technologies and skills that will allow us to better
assess and monitor the health of these critical pieces of
infrastructure? What can be done in the next five or ten years to
improve the data we have on bridges and our ability to correctly
interpret that data? And can we do this while also attending to the
other challenges facing transportation officials such as growing
congestion and deteriorating roadways?
I look forward to hearing your answers and thank you for testifying
today.
I yield back.
Mr. Wu. [Presiding] Thank you very much, Mr. Hall. As
Chairman Gordon referred, on the 1st of August, the whole
country was shocked by the collapse of the I-35 bridge across
Mississippi at Minneapolis, and our condolences and prayers to
all those who were directly affected by that bridge collapse.
But for everybody else around the country, I think that one
thought that must be on folks' minds is, ``What about the
bridges that I drive over? What about my commute to work or
from work?'' These appropriate concerns highlight how much we
have taken our national infrastructure system for granted. Of
the 116,000 or so bridges in the National Highway System, over
6,000 are rated structurally deficient, 80 of these are in my
home State of Oregon, and eight are in my congressional
district. After the I-35 bridge collapse, Congress moved
quickly to offer federal help, and we are now left with a long-
term need to better address how to constantly and consistently
evaluate and repair our national infrastructure. Investing in
research to develop new building materials, new engineering
techniques, and a sufficient technologic toolbox for bridge
inspectors will be critical to our ability to accurately assess
the structural condition of our nation's bridges and to develop
bridge infrastructure that will last for decades and perhaps
even a century with minimal repairs.
The Federal Highway Administration, State highway
administrations, and universities have long been engaged in
surface transportation research in a wide variety of
applications from bridge design to construction to inspection.
However, the transfer of these technologies to end-users has
faced barriers such as the cost of technologies, engineering,
and modeling.
I hope that our witnesses can address these issues.
Also, I hope that our witnesses will discuss the research
and the design capabilities the Federal Government can provide
for State inspectors to accurately rank repair needs. While
inspectors use a variety of methods to determine if a bridge
has an immediate need of repair, the existing methods are
imperfect, and additional research is needed to develop methods
that will provide better quality data on which bridges require
immediate attention.
I look forward to the testimony of our witnesses and their
expertise to help guide this committee in addressing the
research needs to protect our aging infrastructure and what the
Federal Government can do to make sure our citizens do not
question whether or not their daily commute is safe.
[The prepared statement of Chairman Wu follows:]
Prepared Statement of Chairman David Wu
Thank you Mr. Chairman.
Mr. Chairman, on August 1, the country was astonished by the
collapse of the I-35 bridge in Minneapolis, and what was more certain
than the thoughts and prayers on the American people to those affected
was the thought ``What about the bridges I drive over? What about my
commute?''
These are penetrating questions, and these questions highlight that
we take our national infrastructure system for granted.
Of the 116,172 bridges on the National Highway System, 6,175
bridges are rated as structurally deficient. There are 80 of these
bridges in my home state of Oregon are rated as structurally deficient,
and eight are in my district.
In the aftermath of the I-35 bridge collapse Congress moved
immediately with federal dollars. We are now left with the immediate
need to evaluate and repair our national infrastructure. The
overwhelming number of bridges in need of repair, and the associated
cost requires the prioritization of federal and State resources.
Investing in research to develop new building materials, new
engineering techniques and a sufficient toolbox for bridge inspectors
will be critical in our ability to accurately assess the structural
condition of our nation's bridges.
I look forward to the testimony of our witnesses and their
expertise to help guide this committee address the needs of our aging
infrastructure and what the Federal Government can provide to make sure
our citizens do not need to question whether or not their daily commute
is safe.
Mr. Wu. And now I would like to recognize the Ranking
Member of our subcommittee, Dr. Gingrey for his opening
statement.
Mr. Gingrey. Thank you, Chairman Wu, and Ranking Member
Hall. I have some prepared remarks. I can't resist the urge
like most Members to ad lib a little bit here.
I will start out by saying I am certainly proud to be here
with the Rainmaker. I didn't realize that movie was based on
the legislative life of Ralph Hall. That was a very interesting
little bit of information.
Again, Mr. Chairman, I do thank you, and I would like to
start by reiterating as we all have the deep felt sorrow and
concern that we all have for the family members and the loved
ones of those who died in the collapse of the Interstate 35
West bridge in Minneapolis. I believe it was on August 1st of
this year. Our thoughts and prayers continue to go out to the
families of those who lost their lives.
Bridge safety is a growing problem across the country and
includes not just the National Highway System but of course the
many more bridges and the state and local roadways. In my State
of Georgia, as an example, there are 14,500 bridge, 14,500 just
in the State of Georgia, population about 9.4 million people.
One thousand one hundred of these bridges, that is about eight
percent of the total, are ``structurally deficient;'' and
nationally, 12 percent of bridges have received that rating and
in some states it goes up as high as 25 percent structurally
deficient.
Structurally deficient bridges can be found in every part
of the country in the midst of sprawling cities but also out in
the remote areas as Ranking Member Hall indicated and stated in
his remarks. Repairing them will take an enormous effort that
will need the aid of science and technology; and hopefully we
can build advanced structures that are more robust, that are
more reliable, and that will have the ability to detect
potential problems and warn officials electronically.
On the ad lib part, let me just say that 42 years ago, I
was working as a co-op student. I was attending Georgia Tech as
a chemistry major, and I was working at a nuclear plant in
South Carolina. And my job, one quarter, was to run a probe
through a heat exchanger, and I think there were 25 different
channels in that heat exchanger. And you could literally take
these heat exchangers off of the reactor and inspect with this
probe any deterioration or corrosion of the metal, and that was
42 years ago I was doing that. You think about today and walk
in any bathroom almost anywhere, in any city, in any country,
and electronically the commode flushes and the water turns on
and off. So you know, I think it probably is the time, as I
continue with my prepared remarks, that we will be able to do
that in regard to the safety of these bridges and not have to
rely just on physical inspection on a periodic basis. I know
reaching the goal will not be easy. Replacing aging bridges
with new technology, advanced designs, is going to require time
and money that the federal and the State transportation
departments, they don't have it. They don't have it readily at
hand today. We have a strong need for research and development
of low-cost approaches to inspect or rehabilitate bridges.
I am particularly concerned about our current visual
inspection techniques and what can be done to improve this
system in the near future. In the near future. I would like to
draw the panel's attention to this issue. I look forward to
hearing your thoughts. Technology such as embedded sensors
clearly offers dramatically more precise and accurate data.
However, we are a long way from a widespread use of such
systems and will continue to rely on properly trained personnel
to make those final safety determinations, even though as
Chairman Wu indicated or someone at the dais, a year ago, a
year before this tragic accident as I understand it, there was
this physical inspection. And maybe the panelists will be able
to tell us about the recent construction on that bridge to
maybe determine if that had any effect, either.
But we need to have inspection processes and training that
are validated as effective and regularly improved. I am pleased
that we will hear today from Mark Bernhardt, a bridge
inspector. His company has contracts in over 10 states, and he
can give us a sense of what a well-trained individual can do,
but for that matter, what a well-, best-trained individual just
physically can't do.
So I thank the panel for coming before us today, and I look
forward to an enlightening discussion on research and
development in this area.
Thank you, Mr. Chairman. I yield back.
[The prepared statement of Mr. Gingrey follows:]
Prepared Statement of Representative Phil Gingrey
Thank you Mr. Chairman. I'd like to start by reiterating the deep-
felt sorrow and concern that we all have for the family members and
loved-ones of those who died in the collapse of the Interstate 35 West
Bridge in Minneapolis on August 1st of this year. Our thoughts and
prayers are with them.
Bridge safety is a growing problem across the country and includes
not just the National Highway System, but State and local roadways as
well. In my State of Georgia, for example, there are 14,523 bridges.
1,113 of these bridges, or about eight percent, are ``structurally
deficient.'' Nationally, 12 percent of bridges have received this
rating and some states have as high as 25 percent of their bridges
listed as ``structurally deficient.''
Structurally deficient bridges can be found in every part of the
country, in the middle of sprawling cities and in remote wildlands.
Repairing them will take an enormous effort that will need the aid of
science and technology. Hopefully, we can build advanced structures
that are more robust, more reliable and that will have the ability to
detect potential problems and warn officials electronically. Reaching
this goal will not be easy, however. Replacing aging bridges with new,
technologically enhanced designs will require time and money that
federal and State transportation departments DO NOT have readily at
hand. We have a STRONG need for research and development of low-cost
approaches to inspect or rehabilitate bridges.
I am particularly CONCERNED about our current visual inspection
techniques and what can be done to improve this system in the near
future. I'd like draw the panel's attention to this issue and look
forward to hearing your thoughts. Technology such as embedded sensors
clearly offers dramatically more PRECISE and ACCURATE data. However, we
are a long way from widespread use of such systems and will continue to
rely on properly trained personnel to make final safety determinations.
We need to have inspection processes and training that are validated as
effective and regularly improved. I'm pleased that we'll hear today
from Mark Bernhardt, a bridge inspector whose company has contracts in
over 10 states and who can give us a sense of what a well-trained
individual can do and for that matter, what a trained individual cannot
do.
I thank the entire panel for coming before us today, and look
forward to an enlightening discussion on Research & Development in this
area. Thank you and I yield back.
Mr. Wu. Thank you, Dr. Gingrey. If there are Members who
wish to submit additional opening statements, your statement
will be added to the record at this point.
[The prepared statement of Mr. Costello follows:]
Prepared Statement of Representative Jerry F. Costello
Thank you, Mr. Chairman. I am pleased to be here today as we
examine research and development measures to address structurally
deficient bridges in the United States. I would like to welcome today's
witnesses.
The tragic bridge collapse that occurred on August 1, 2007, in
Minneapolis, MN, serves as a wake up call that we must properly invest
in maintaining our infrastructure, which includes the tools needed to
evaluate and monitor its condition.
While we have a first-class transportation system, it is in many
instances nearing the end of its life expectancy, and we have neglected
to upgrade and modernize our infrastructure over the years.
For example, our Interstate Highway System is almost 50 years old.
Thirty-two percent of our major roads are in poor or mediocre
condition; one of every eight bridges is structurally deficient; and 36
percent of the Nation's urban rail vehicles and maintenance facilities
are in substandard or poor condition.
While the need for construction upgrades and renovations are
apparent, we must also recognize the vital need for technological
advancements in tools and methods to safely, accurately, and
economically evaluate these structures.
We should not build our infrastructure and then walk away without
maintaining, evaluating, and modernizing it as it becomes unsafe. I
supported a $375 billion highway bill that was advocated by a 2002
Department of Transportation report because I strongly believe that our
infrastructure must be a top priority. We were able to pass a $286.4
billion bill; however, that is not enough to meet our needs. According
to DOT, more than $65 billion could be invested immediately by all
levels of government, to replace or otherwise address existing bridge
deficiencies.
While we have programs and money specifically established in the
highway bill for bridge improvements and repairs, money is allowed to
be transferred and rescinded to other accounts. That inhibits
completion of important projects, including making sure our bridges are
structurally sound.
We must find a way to make the necessary improvements to our roads
and bridges to make sure the highest level of safety is maintained and
that the U.S. economy remains strong. As we have not kept up with the
maintenance and upkeep of our bridges, it is even more vital to develop
advanced technologies to evaluate and monitor current bridge
structures. I am interested in hearing the thoughts and ideas of our
witnesses on these topics.
I look forward to today's hearing as we examine these important
issues.
[The prepared statement of Mr. Carnahan follows:]
Prepared Statement of Representative Russ Carnahan
Mr. Chairman, thank you for hosting this hearing to examine
research and development activities to improve bridge safety through
enhanced structural engineering and inspection technologies.
As increasing traffic loads take their toll on America's
transportation infrastructure, the Nation's bridges are plagued by
growing structural deficiencies that range from paving issues to
serious, life-threatening flaws. Numerous analysts over the past few
years have concluded that more than twelve percent of the country's
bridges will require urgent repairs over the next several years, at a
cost of nearly $200 billion. The challenge facing policy-makers and
inspectors is to determine how to allocate limited funding to the
bridges in greatest need of repair.
The tragic collapse of Interstate 35W in Minnesota brought our
attention to a widespread problem that affects every community. In my
home State of Missouri, nearly 8,000 bridges have been identified as
structurally deficient or functionally obsolete, including 125
Interstate Highway bridges. The total average daily traffic over
structurally deficient interstate bridges in Missouri is 3,280,648
vehicles.
Moreover, the Federal Highway Administration has listed eight
bridges on the National Highway System in my district (MO-3) to be
structurally deficient. These bridges include: I-55 North at Hillsboro
Road in Jefferson County, I-64 East at Laclede Station Road in St.
Louis County, I-64 East at Clayton Terrace in St. Louis County, I-64
East at McCausland Ave in St. Louis City, I-44 West at Kingshighway
Blvd. in St. Louis City, I-55 North at 2nd Street in St. Louis City, I-
64 West at I-55 in St. Louis City and I-64 East at I-55 in St. Louis
City.
Improving bridge safety is imperative. While I believe we must
direct more resources towards our nation's infrastructure, it is also
crucial that we direct our attention to the subject of today's hearing,
improving technology for bridge design, maintenance, and inspection,
and reviewing current methods of collaboration and technology transfer
between the research community and State highway administrations. I am
eager to hear our witnesses' assessments of bridge-related innovation
and research priorities. Your first-hand experiences are vital to
maintaining our nation's infrastructure.
To all the witnesses--thank you for taking time out of your busy
schedules to appear before us today. I look forward to hearing your
testimony.
[The prepared statement of Mr. Melancon follows:]
Prepared Statement of Representative Charlie Melancon
Thank you Chairman Gordon and Ranking Member Hall for holding this
important hearing on bridge safety. Since the collapse of the I-35
bridge in Minnesota, many Americans have questioned the safety of the
bridges they cross every day, but this is only one part of a much
larger issue. The tragedy in Minnesota emphasizes the importance of not
just bridge safety, but the safety of our entire public infrastructure
system.
Americans depend on public infrastructure every day and they
deserve to be confidant that their tax dollars are being used to make
them safe during their commutes and in their communities. As their
elected representatives in government, it is our job to promote this
security by ensuring that all elements of public infrastructure--
bridges, roads, dams, and levees--are up to code.
These are needs--not wants. The United States cannot prosper and
grow without safe, reliable public infrastructure. We only have to look
to our recent past for proof. As we saw after Hurricane Katrina, the
manmade disaster caused by the levee failures was more disastrous to
New Orleans and south Louisiana than the damage inflicted by the
hurricane. It was the levee failures that made Katrina the most costly,
and one of the most deadly, disasters in U.S. history.
I applaud this committee for its work to ensure that our bridges
are safe. However, I hope that the work does not end there. Let us take
this opportunity to begin studying the safety of all the elements of
our public infrastructure system--bridges, roads, dams and, not least
of all, levees. We owe it to the American public to make sure they have
reason to feel safe again.
Thank you and I yield back my time.
[The prepared statement of Mr. Mitchell follows:]
Prepared Statement of Representative Harry E. Mitchell
Mr. Chairman,
Thank you for convening this morning's hearing.
All of us extend our deepest sympathies to the Minneapolis
community and to the loved ones who died or were injured in the I-35
West Bridge collapse.
This is the second hearing in which I have participated
investigating this tragic accident. The Transportation and
Infrastructure Committee, on which I also serve, held a hearing on the
causes of the accident two weeks ago.
I am pleased that Chairman Gordon has called us here today to look
at the issue from a different perspective. . .that of the current state
of bridge safety-related research.
Of the 600,000 bridges in the U.S., 73,764, or more than 12
percent, of them are considered to be deficient. One of those bridges
included the I-35 West Bridge in Minneapolis. The American Society of
Civil Engineers rates the Nation's bridge infrastructure by the letter
grade of ``C.'' I am glad to report that ASCE gave Arizona an
``Aminus'' for highway bridge safety.
Arizona is a growing state and a good deal of our infrastructure is
new. It is an arid state, and as a result, our bridges are subject to
fewer corrosive factors such as moisture.
Of the 7,248 bridges in Arizona, 161 are considered deficient.
Arizona residents want assurances that the bridges they travel across
are safe and sturdy structures. Last month, I accompanied
representatives of Arizona's State Department of Transportation. We
toured the Loop 202 bridge over 56th Street, and they walked me through
the inspection process. I came away from that tour with a better
appreciation of the inspection process. The inspection protocols are
both time consuming and expensive.
We need to explore ways and techniques by which we can detect
structural deficiencies earlier, more accurately and within reasonable
costs. For the most part, the inspection process provides engineers
with only a ``snapshot'' of bridge conditions. We look to research
projects and technological developments that will enable us to assess
bridge conditions over a longer span of the infrastructure's life
cycle.
Today's hearing will provide us with some ideas on the appropriate
methods to conduct relevant research and development into
infrastructure research and innovation.
Thank you, Mr. Chairman.
Mr. Wu. I am deeply pleased to have such an expert group of
witnesses before the Committee today to discuss this very
important topic. Mr. Dennis Judycki is the Associate
Administrator for Research, Development, and Technology at the
Federal Highway Administration and Director of the U.S. DOT's
Turner-Fairbank Highway Research Center. With him is Mr.
Benjamin Tang, Principal Bridge Engineer for the Office of
Bridge Technology at the FHA. Mr. Harry Lee James is the Deputy
Executive Director and Chief Engineer for the Mississippi
Department of Transportation. Dr. Kevin Womack is a Director of
the Utah Transportation Center and Professor of Civil and
Environmental Engineering at Utah State University. Finally, we
have Mr. Mark Bernhardt, Director of Facility Inspection for
Burgess & Niple, an engineering firm in Ohio. Thank you all for
being here.
As our witnesses already know, spoken testimony is to be
limited to five minutes each. Your written statements will be
entered into the record, and after this period, Members of the
Committee will have five minutes each to ask questions. And we
will begin with Mr. Judycki. Please proceed.
STATEMENT OF MR. DENNIS C. JUDYCKI, ASSOCIATE ADMINISTRATOR,
RESEARCH, DEVELOPMENT, AND TECHNOLOGY, FEDERAL HIGHWAY
ADMINISTRATION, U.S. DEPARTMENT OF TRANSPORTATION; ACCOMPANIED
BY MR. BENJAMIN TANG, PRINCIPAL BRIDGE ENGINEER/TEAM LEADER,
OFFICE OF BRIDGE TECHNOLOGY, FEDERAL HIGHWAY ADMINISTRATION,
U.S. DEPARTMENT OF TRANSPORTATION
Mr. Judycki. Thank you, Mr. Chairman. Members, it is a
pleasure to be here. I am pleased to report today on Federal
Highway's research, development, and technology activities that
enhance our highway bridges. And as you mentioned, Mr.
Chairman, joining me today is Benjamin Tang, the Principal
Bridge Engineer with the Federal Highway Administration.
As you have mentioned, America was stunned by the collapse
of the I-35 bridge in Minneapolis. The cause of the failure is
still unknown, and Federal Highways is assisting the National
Transportation Safety Board in their investigation of the
collapse.
Several Turner-Fairbank Highway Research Center experts
are, as we speak, on site helping with the forensic work.
Others are developing a computer model to evaluate the behavior
of the bridge. Although examination of the physical members of
the bridge being recovered from the site provides the best
evidence of why the bridge collapsed, the computer allows
simulation and evaluation of multiple failure scenarios, which
can be evaluated against the actual bridge failure and physical
forensic evidence.
We are committed to helping the NTSB complete its work as
quickly as possible, but certainly, as you can appreciate, must
take the time to fully understand what happened so that we can
be sure that this tragedy will not happen again.
Federal, State, and local transportation agencies consider
the inspection of the Nation's nearly 600,000 bridges to be of
vital importance and invest significant funds in bridge
inspection technologies and techniques for which have been
evolving for the last 30 years since the establishment of the
National Bridge Inspection Standards. Commonly used methods for
evaluating concrete members during ``routine'' inspections
include mechanical sounding to identify areas of delamination
and degradation. Similarly for steel members, routine methods
include cleaning and scraping, and the use of various tests to
identify cracking and areas of significant corrosion. More
state-of-the art methods utilized during in-depth inspections
for concrete and steel bridges include impact echo, infrared
thermology, ground-penetrating radar, and ultrasonic methods.
There are numerous other technologies under development
that have the potential to substantially advance the practice
of bridge inspection. Unfortunately, there is no one-size-fits-
all approach for use of non-destructive evaluation testing.
Each technology is designed for a specific purpose and for a
specific function. Federal highways, state DOTs, university
transportation centers, and industries continue to investigate
and improve the practicality in advancing these technologies.
There are also a number of monitoring systems that can be
used to provide real-time data and alert bridge owners to such
things as threshold stresses in load-carrying members,
excessive movement, crack growth, or scour around a bridge
pier. However, monitoring systems don't eliminate the need for
regular visual inspections, nor do they ensure that failure of
a bridge component will not occur.
Federal Highways is actively coordinating a National Bridge
Research Program with our partners and stakeholders, and our
research and development efforts include not only promising
advanced non-destructive evaluation technologies for
inspection, but also long-term bridge performance and high
performance structures and innovative materials.
The current Federal Highway Bridge Research Program is
focused on effective stewardship and management of bridge
infrastructure, assuring of a high level of safety and security
for highway bridges, and thirdly, developing the ``Bridge of
the Future.''
FHWA's responsibility for research and technology
encompasses not only managing and conducting research and
sharing the result but certainly supporting and facilitating
technology and innovation deployment. This includes working
with University Transportation Centers, others in academia, the
State DOTs, industry, and the Transportation Research Board.
FHWA also utilizes its Local Technical Assistance Program
as a mechanism for transferring technologies to State and local
agencies, and education and training programs provided through
our National Highway Institute help introduce new technologies
and raise the state of the practice. Ultimately, though, a key
measure of success for any highway technology innovation
depends on the acceptance and adoption by stakeholders.
It is Federal Highway's ongoing responsibility to continue
to advance the state-of-the-art through research and
development and to work with our partners to raise the state-
of-the-practice in bridge engineering.
I would like to thank you again for the opportunity to
testify and will be pleased to answer any questions that you
may have.
[The prepared statement of Mr. Judycki and Mr. Tang
follows:]
Prepared Statement of Dennis Judycki and Benjamin Tang
Mr. Chairman and Members, we are pleased to appear before you today
to report on the Department of Transportation's research, development,
testing, and evaluation activities, as administered by the Federal
Highway Administration (FHWA), to ensure the safety of the Nation's
highway bridges. This is a very important hearing topic in the wake of
the tragic collapse of the Interstate 35 West (I-35W) bridge over the
Mississippi River in Minneapolis, Minnesota. On behalf of the
Department, we extend our deepest sympathy to the loved ones of those
who died and to the injured.
Minnesota Bridge Collapse
America was stunned by the collapse of the I-35W bridge at
approximately 6:00 PM, Central Daylight Time, on Wednesday, August 1,
2007. Numerous vehicles were on the bridge at the time and there were
13 fatalities and 123 people injured. The I-35W bridge originally
opened in November 1967 and became one of the critical facilities in a
vital commercial and commuting corridor. The bridge was an eight-lane,
steel deck truss structure that rose 64 feet above the Mississippi
River. The main span extended to 456 feet in length to avoid putting
piers in the water which would have impeded river navigation. As of the
2004 count, an estimated 141,000 vehicles traveled per day on the
bridge.
We do not yet know why the I-35W bridge failed, and the Department
is working closely with the National Transportation Safety Board (NTSB)
as it continues its investigation to determine the cause or causes. In
the interim, we are taking every step to reassure the public that
America's infrastructure is safe. The Secretary of Transportation has
issued two advisories to States in response to what has been learned so
far, asking that States re-inspect their steel deck truss bridges and
that they be mindful of the added weight construction projects may
bring to bear on bridges.
The Federal Highway Administration is assisting the NTSB in a
thorough investigation, which includes a structural analysis of the
bridge. Within days of the collapse, development of a computer model
based upon the original design drawings for the bridge began at FHWA's
Turner-Fairbank Highway Research Center in McLean, Virginia. This model
can perform simulations to determine the effect on the bridge of
removing or weakening certain elements to recreate, virtually, the
actual condition of the bridge just prior to and during the bridge's
collapse.
By finding elements that, if weakened or removed, result in a
bridge failure similar to the actual bridge failure, the investigators'
work is considerably shortened. While examination of the physical
members of the bridge being recovered from the site provides the best
evidence of why the bridge collapsed, the analytical model allows the
evaluation of multiple scenarios which can then be validated against
the physical forensic evidence. We are committed to accomplishing this
work as quickly as possible, but it is expected to take several months.
Our experts will continue to be there, on the ground in Minneapolis, to
provide assistance. We need to fully understand what happened so we can
take every possible step to ensure that such a tragedy does not happen
again. Data collected at the accident scene, with the help of the
Federal Bureau of Investigation's 3-D laser scanning technology, is
being used to assist in the investigation.
Federal, State, and local transportation agencies consider the
inspection of our nearly 600,000 bridges to be of vital importance and
invest significant funds in bridge inspection activities each year. We
strive to ensure that the quality of our bridge inspection program is
maintained at the highest level and that our funds are utilized as
effectively as possible. On August 2, the day after the collapse,
Secretary of Transportation Mary E. Peters requested the Department of
Transportation's Inspector General to conduct a rigorous assessment of
the federal-aid bridge program and the National Bridge Inspection
Standards (NBIS).
National Bridge Inspection Program
The National Bridge Inspection Program was created in response to
the collapse, in 1967, of the Silver Bridge over the Ohio River between
West Virginia and Ohio, which killed 46 people. At the time of that
collapse, the exact number of highway bridges in the United States was
unknown, and there was no systematic bridge inspection program to
monitor the condition of existing bridges. In the Federal-aid Highway
Act of 1968, Congress directed the Secretary of Transportation in
cooperation with State highway officials to establish: (1) NBIS for the
proper safety inspection of bridges, and (2) a program to train
employees involved in bridge inspection to carry out the program. As a
result, the NBIS regulation was developed, a bridge inspector's
training manual was prepared, and a comprehensive training course,
based on the manual, was developed to provide specialized training. To
address varying needs and circumstances, State and local standards are
often even more restrictive than the national standards.
The NBIS require safety inspections at least once every 24 months
for highway bridges that exceed 20 feet in total length located on
public roads. Many bridges are inspected more frequently. However, with
the express approval by FHWA of State-specific policies and criteria,
some bridges can be inspected at intervals greater than 24 months. New
or newly reconstructed bridges, for example, may qualify for less
frequent inspections. Approximately 83 percent of bridges are inspected
once every 24 months, 12 percent are inspected annually, and five
percent are inspected on a 48-month cycle.
The State transportation department (State DOT) must inspect, or
cause to be inspected, all highway bridges on public roads that are
fully or partially located within the State's boundaries, except for
bridges owned by federal agencies. States may use their Highway Bridge
Program funds for bridge inspection activities. Privately owned
bridges, including commercial railroad bridges and some international
crossings, are not legally mandated to adhere to the NBIS requirements;
however, many privately owned bridges on public roads are being
inspected in accordance with the NBIS.
For bridges subject to NBIS requirements, information is collected
on bridge composition and conditions and reported to FHWA, where the
data is maintained in the National Bridge Inventory (NBI) database. The
NBI is essentially a database of bridge information that is ``frozen''
at a given point in time. This information forms the basis of, and
provides the mechanism for, the determination of the formula factor
used to apportion Highway Bridge Program funds to the states. A
sufficiency rating (SR) is calculated based on the NBI data items on
structural condition, functional obsolescence, and essentiality for
public use. The SR is then used programmatically to determine
eligibility for rehabilitation or replacement using Highway Bridge
Program funds.
Bridge inspection techniques and technologies have been
continuously evolving since the NBIS were established over 30 years ago
and the NBIS regulation has been updated several times as Congress has
revised the inspection program and its companion program, the Highway
Bridge Program (formerly Highway Bridge Replacement and Rehabilitation
Program). The most recent NBIS revision took effect in January 2005.
The bridge inspector's reference manual has been updated as well, and
we have developed, through our National Highway Institute (NHI), an
array of bridge inspection training courses.
There are five basic types of bridge inspections--initial, routine,
in-depth, damage, and special. The first inspection to be completed on
a bridge is the ``initial'' inspection. The purpose of this inspection
is to provide all the structure inventory and appraisal data, to
establish baseline structural conditions, and to identify and list any
existing problems or any locations in the structure that may have
potential problems. The ``routine'' inspection is the most common type
of inspection performed and is generally required every two years. The
purpose of ``routine'' inspections is to determine the physical and
functional condition of a bridge on a regularly scheduled basis. An
``in-depth'' inspection is a close-up, hands-on inspection of one or
more members above or below the water level to identify potential
deficiencies not readily detectable using routine inspection
procedures. A ``damage'' inspection is an emergency inspection
conducted to assess structural damage immediately following an accident
or resulting from unanticipated environmental factors or human actions.
Finally, a ``special'' inspection is used to monitor, on a regular
basis, a known or suspected deficiency.
Safety is enhanced through these inspections and by ``rating''
bridge components, such as the deck, superstructure, and substructure,
and by the use of non-destructive evaluation (NDE) methods and other
advanced technologies. Visual inspection is the primary method used to
perform routine bridge inspections, and tools for cleaning, probing,
sounding, and measuring, and visual aids are typically used. On
occasion, destructive tests are conducted to evaluate specific areas or
materials of concern, or to help identify appropriate rehabilitative
work. Type, location, accessibility, and condition of a bridge, as well
as type of inspection, are some of the factors that determine what
methods of inspection practices are used. When problems are detected,
or during the inspection of critical areas, more advanced methods are
employed.
Commonly used methods for evaluating concrete elements during
``routine'' inspections include mechanical sounding to identify areas
of delamination (the separation of a layer of concrete from the
reinforcing steel in the concrete member) and other forms of concrete
degradation. Similarly, for the ``routine'' inspection of steel
members, methods include cleaning and scraping, and the use of dye
penetrant and magnetic particle testing to identify cracking and areas
of significant corrosion.
State-of-the-art methods utilized during ``in-depth,'' ``damage,''
and ``special'' inspections include impact echo, infrared thermography,
ground penetrating radar, and strain gauges for concrete structures and
elements, and ultrasonic, eddy current, radiography, acoustic
emissions, strain gauges, and x-ray technology for steel structures and
elements.
There are numerous other technologies under development that have
the potential to substantially advance the practices used for bridge
inspection. Some of these technologies are also being developed or are
in limited use by other industries, such as the aerospace and nuclear
industries. There is no one-size-fits-all approach in the use of non-
destructive evaluations and testing; each technology is designed for a
specific purpose and function. Although these developing technologies
have the potential to augment and advance bridge inspection practice,
the challenge is to find a way to make them efficient, effective, and
practical for field use. FHWA, industry, academia, the Transportation
Research Board (TRB), and State DOTs continue to investigate and
improve the practicality of many of these technologies. As a result of
these efforts, a number of systems have recently become available that
can assist an inspector in the identification and quantification of
such things as reinforced concrete deterioration, steel tendon
distress, and the displacement or rotation of critical members in a
bridge.
There are also a number of monitoring systems that can be used to
provide real time data and alert the bridge owner to such things as
failure of load carrying members, excessive rotation or displacement of
an element, overload in a member, growth of a crack, or scour around a
bridge pier. The type of information provided by these systems is
either very specific and provides detailed information on isolated
areas or members of the bridge, or rather generic and provides general
bridge behavior information. The most practical of these systems are
being used by owners following an ``in-depth'' or ``special''
inspection, to monitor the performance of the element or the bridge,
when some specific concern has been raised but the concern is not
considered to be a short-term safety hazard. However, the effectiveness
and costs associated with monitoring systems must be weighed against
the benefits gained. Like any emerging technology, changes and updates
in monitoring systems can become a big challenge to maintain
economically over the long haul. Today, bridges are being built to last
75 to 100 years and installing any new monitoring systems and expecting
them to be durable and serviceable for such a long period has never
been done before. Monitoring systems that are available today require
routine maintenance and repair, and continuous assessment to ensure
that they are working correctly. In addition, they do not eliminate the
need for regular visual inspections. In many circumstances, it is more
effective to increase the inspection frequency, repair or retrofit
areas of concern, or replace the structure.
Since 1994, the percentage of the Nation's bridges that are
classified as ``structurally deficient'' has declined from 18.7 percent
to 12.1 percent. The term ``structurally deficient'' is a technical
engineering term used to classify bridges according to serviceability,
safety, and essentiality for public use. Bridges are considered
``structurally deficient'' if significant load-carrying elements are
found to be in poor or worse condition due to deterioration or damage,
or the adequacy of the waterway opening provided by the bridge is
determined to be extremely insufficient to the point of causing
intolerable traffic interruptions. The fact that a bridge is classified
as ``structurally deficient'' does not mean that it is unsafe for use
by the public.
These infrastructure quality numbers for bridges should, and can,
be improved, but it is inaccurate to conclude that the Nation's
transportation infrastructure is unsafe. We have quality control
systems that provide surveillance over the design and construction of
bridges. We have quality control systems that oversee the operations
and use of our bridges. And we have quality control over inspections of
bridges to keep track of the attention that a bridge will require to
stay in safe operation. These systems have been developed over the
course of many decades and are the products of the best professional
judgment of many experts. We will ensure that any findings and lessons
that come out of the investigation into the I-35W bridge collapse are
quickly learned and appropriate corrective actions are
institutionalized to prevent any future occurrence.
Bridge Research and Technology Programs
The current FHWA bridge research program is focused on three areas:
(1) the ``Bridge of the Future,'' (2) effective stewardship and
management of the existing bridge infrastructure in the United States,
and (3) assuring a high level of safety, security, and reliability for
both new and existing highway bridges and other highway structures.
The ``Bridge of the Future'' is intended to be a bridge that can
last for 100 years or more, and require minimal maintenance and
repair--while being adaptable to changing conditions, such as
increasing loads or traffic volumes. FHWA's bridge research and
technology (R&T) programs are focusing on improving the long-term
performance of our nation's highway infrastructure in an effective yet
economical way.
In the Safe, Accountable, Flexible, Efficient Transportation Equity
Act: A Legacy for Users (SAFETEA-LU), Congress authorized and funded
research in five program areas: long-term bridge performance,
innovative bridge delivery, high performance and innovative materials,
nondestructive inspection technology, and seismic research. The
specific programs authorized by SAFETEA-LU are summarized in the
following:
Long-Term Bridge Performance
Long-Term Bridge Performance Program (LTBPP)--The LTBPP has been
designed as a 20-year effort that will include detailed inspections and
periodic evaluations and testing on a representative sample of bridges
throughout the United States in order to monitor and measure their
performance over an extended period of time. The program will collect
actual performance data on deterioration, corrosion, or other types of
degradation; structural impacts from overloads; and the effectiveness
of various maintenance and improvement strategies typically used to
repair or rehabilitate bridges. The resulting LTBPP database will
provide high quality, quantitative performance data for highway bridges
that will support improved designs, improved predictive models, and
better bridge management systems.
Innovative Bridge Delivery
Innovative Bridge Research and Deployment (IBRD) Program--The IBRD
program encourages highway agencies to more rapidly accept the use of
new and innovative materials and technologies or practices in highway
structure construction by promoting, demonstrating, evaluating, and
documenting the application of innovative designs, materials, and
construction methods in the construction, repair, and rehabilitation of
bridges and other structures. This will increase safety and durability
and reduce construction time, traffic congestion, maintenance costs,
and life-cycle costs of bridges.
High-Performance and Innovative Materials
High-Performance Concrete (HPC) Research and Deployment Program--The
HPC program is a subset of the IBRD program. It continues the
advancement of HPC applications through targeted research that
addresses needed improvements in design, fabrication, erection, and
long-term performance in order to achieve the Bridge Program strategic
outcomes. HPC research focuses on material and casting issues,
including improved performance criteria, lightweight concrete, curing,
and test methods; structural performance concerns, including
compression, shear, and fatigue behavior for both seismic and non-
seismic applications; and concepts related to accelerated construction
and bridge system design and performance.
High-Performing Steel (HPS) Research and Technology Program--The HPS
research and technology transfer program is focused on resolving a
number of issues and concerns with the design, fabrication, erection,
and long-term performance of both conventional and High Performance
steels. The program focuses research and technology transfer and
education in the areas of materials and joining (for example, optimized
welding processes and procedures); long-term performance (including
advanced knowledge on performance limitations of weathering steels and
the potential development of a 100-year shop-applied permanent steel
coating system); innovative design (including testing and deployment of
modular steel bridge super- and substructure systems); and fabrication
and erection tools and processes.
Ultra-High-Performance Concrete (UHPC) Research and Technology--UHPC is
a unique material which is reinforced with short steel fibers, but
requires no conventional steel reinforcing. Prior FHWA research on UHPC
focused on basic material characterization, and the development of
optimized structural systems using this very high performance, but
costly, material. Under the UHPC program, additional work will be
conducted to further understand the unique structural properties of
this material and assess its corrosion-resistance properties, while
addressing its use in other structural components including pre-cast
bridge deck panels and pre-stressed I- and bulb-tee girders.
Wood Composite Research--The University of Maine is conducting a
research program focused in the development and application of wood/
fiber reinforced polymer (FRP) composite materials for potential use as
primary structural members in highway bridges.
Non-destructive Inspection Technology
Steel Bridge Testing Program--This program is focused on the further
development and deployment of advanced NDE tools that can be used to
detect and quantify growing cracks in steel bridge members and welds.
As described in SAFETEA-LU, the NDE technology should ultimately be
able to detect both surface and subsurface cracks, in a field
environment, for flaws as small as 0.010 inches in length or depth.
Seismic Research
Seismic Research Program--The University of Nevada, Reno, and the State
University of New York at Buffalo are conducting a seismic research
program intended to increase the resilience of bridges and reduce
earthquake-induced losses due to highway damage.
FHWA is also conducting and managing a number of other important
bridge research projects in conjunction with various partners and
stakeholder groups, all focused on improving the performance and
durability of our Nation's highway bridges--both those exposed to
normal everyday traffic and use, and those exposed to the damaging
effects of extreme natural and man-made hazards.
In addition to FHWA, there are a number of other organizations that
sponsor bridge research, and a much larger group of agencies that
conduct bridge R&T. These include State DOTs, industry, other federal
agencies, and academia. Other transportation modes also conduct limited
bridge research, including the railroad industry.
FHWA actively coordinates the National research program with our
partners and stakeholders for agenda-setting, and in the conduct of
research and delivery of new innovations. Our staff participates in
numerous national and international organizations and serves on
committees focused on bridge research, development, and technology
transfer. We organize formal technical advisory groups and technical
working groups, comprised of federal, State, and local transportation
officials; bridge engineering consultants and industry groups; and
academia to assist in the design, conduct, and delivery of the program.
An important R&T partner for FHWA is the University Transportation
Centers (UTC) Program, managed by the Research and Innovative
Technology Administration (RITA). FHWA works with the UTCs to identify
opportunities for collaboration that will increase knowledge and skills
among State and local highway agencies. FHWA holds periodic workshops
that bring together researchers and practitioners from FHWA, State
DOTs, TRB, and UTCs to learn about each others' interests and
capabilities, new research opportunities, and technologies under
development. FHWA held an infrastructure workshop for UTCs and State
DOTs at Turner-Fairbank Highway Research Center in March 2007. FHWA is
working with a number of UTCs on transportation research, including the
University of Tennessee, the University of Minnesota, Utah State
University, Rutgers, and the University of Missouri-Rolla. RITA also
consolidates bridge technology information from all the Department's
modal administrations to assist us in having the best available
technologies.
State and local highway agencies learn of new technologies
developed by UTCs through a variety of events sponsored by FHWA. These
include annual workshops show-casing the results of UTC research on
particular topics, and numerous conferences, seminars and workshops co-
sponsored with specific UTCs (for example, the ``Self Consolidating
Concrete Workshop'' at South Dakota State University). FHWA also
utilizes its highly successful Local Technical Assistance Program
(LTAP) as a mechanism for transferring technologies developed through
the UTC program to State and local highway agencies, and tribal
governments.
FHWA is also an active participant with the American Association of
State Highway and Transportation Officials (AASHTO) in technology
transfer such as the AASHTO Technology Implementation Group and the
Joint AASHTO/FHWA/National Cooperative Highway Research Program
International Technology Exchange Program, more commonly known as the
International Scanning Program. Recent scans have included a scan on
bridge management, and a follow-on scan in 2007 on Bridge Evaluation
Quality Assurance. The 2007 scan identified and explored bridge
inspection processes in use in European countries.
Ultimately, a key measure of success of any highway technology
depends on its acceptance by stakeholders on a national scale. FHWA's
responsibilities for R&T include not only managing and conducting
research, but also sharing the results of completed research projects,
and supporting and facilitating technology and innovation deployment.
FHWA's Resource Center is a central location for obtaining highway
technology deployment assistance. (The multiple services offered by the
Resource Center are listed at www.fhwa.dot.gov/resourcecenter/.)
Education and training programs are provided through the FHWA NHI
(www.nhi.fhwa.dot.gov).
There are a number of barriers to technology deployment that may
explain the relatively slow adoption of highway technologies that
appear cost effective. Lack of information about new technologies is
one barrier that may be overcome with information and outreach
programs. Long-standing familiarity with existing technologies gained
through education or experience also may hamper the adoption of newer
technologies. Education and training programs provided through the NHI
often help to transcend these types of barriers.
It also may be difficult for stakeholders to envision the long-
range benefits of a new technology relative to initial investment
costs, especially if the payback (break-even) period is long. Even if
stakeholders are aware of eventual cost savings from a more efficient
or effective highway technology, they may have confidence in
traditional ways of, for example, assessing pavement performance.
Demonstration projects that provide hard quantitative data can help tip
the scales so that stakeholders are more willing to try and eventually
regularly use innovative technologies.
Despite these efforts, technology deployment is also slowed by
residual uncertainties about performance, reliability, installation,
and maintenance costs; availability of the next generation of the
technology; and the need for the necessary technical and physical
infrastructure to support the technology in question. These persistent
barriers can be addressed with outreach programs and collaborative
efforts with stakeholders--ranging from the TRB to researchers within
State DOTs--as well as other incentives to enhance the cost
effectiveness of new technologies. Taken together, these initiatives
often encourage earlier and broader adoption of highway technologies by
increasing stakeholder familiarity with new technologies.
One such program is FHWA's Highways For LIFE. (http://
www.fhwa.dot.gov/hfl/hflfact.cfm). The purpose of Highways for LIFE is
to advance long lasting highways using innovative technologies and
practices to accomplish fast construction of efficient and safe
pavements and bridges, with the overall goal of improving the driving
experience for America. The program includes demonstration construction
projects, stakeholder input and involvement, technology transfer,
technology partnerships, information dissemination, and monitoring and
evaluation. The innovative technologies that the Highways for LIFE
program promotes include prefabricated bridge elements and systems,
road safety audits, and tools and techniques for ``Making Work Zones
Work Better.''
Perhaps the main barrier to technology deployment is the general
lack of incentive mechanisms to encourage the deployment of new
technologies. We need to develop better incentive mechanisms in the way
the program is designed, the way we procure, and the extent to which we
rely on the private sector.
The Missouri Safe and Sound Bridge Improvement Project provides an
example of a potentially innovative way to improve incentives and
encourage innovation and private sector participation.
On May 25, 2007 the Department of Transportation approved a $600
million allocation of Private Activity Bonds to the Missouri DOT for
the Missouri Safe and Sound Bridge Improvement Project. The allocation
will be made available to two short-listed bidders who are competing
for a contract to bring 802 of Missouri's lowest rated bridges up to
satisfactory condition by December 2012 and keep them in that condition
for at least 25 years. The contract will be awarded largely on the
basis of the lowest level of ``availability payments'' that the bidder
will accept to improve and maintain the 802 bridges. Missouri DOT will
use federal formula funds to pay the availability payments.
SATETEA-LU authorized $15 billion in Private Activity Bonds. These
bonds provide tax-exempt financing for private firms to carry out
highway and surface freight transfer projects. This innovative
financing approach will allow Missouri to complete these much needed
bridge improvements more quickly and, it is hoped, at a lower cost.
Other States, including Pennsylvania and North Carolina, are also
interested in this innovative approach.
Through these and other mechanisms, FHWA supports the development
and implementation of innovative technology deployment practices and
processes throughout the highway community.
Conclusion
The I-35W bridge collapse was both a tragedy and wake-up call to
the country. The Department's Inspector General will be monitoring all
of the investigations into the collapse and reviewing our inspection
and funding programs to decide and advise us what short- and long-term
actions we may need to take to improve the program. Though we will have
to wait for the NTSB's report before we really know the cause of the
collapse, a top-to-bottom review is underway to make sure that
everything is being done to keep this kind of tragedy from occurring
again. The public deserves to know and trust that our Nation's highways
are safe.
We look forward to continuing to work with Congress to give the
people of this Nation the safe, efficient, and effective transportation
system that they expect and deserve.
Thank you again for this opportunity to testify. We will be pleased
to answer any questions you may have.
Biography for Dennis C. Judycki
Dennis Judycki is the Associate Administrator for Research,
Development & Technology (RD&T), a position held since January 1999. In
this position, he is Director of FHWA's Turner-Fairbank Highway
Research Center (TFHRC) in McLean, Virginia, and is responsible for
leadership in the development and coordination of national research and
technology partnerships, corporate facilitation and coordination of the
delivery of technology and innovation, and the formulation, conduct and
evaluation of research and development. Pending the appointment of an
Executive Director, Mr. Judycki served as the FHWA Deputy Executive
Director for two months at the end of 2001.
Prior to his RD&T appointment, Mr. Judycki held the position of
Associate Administrator for Safety & System Applications (SSA),
responsible for the FHWA programs in technology and innovation
application, highway safety, traffic management and intelligent
transportation system (ITS), and training through the National Highway
Institute.
Mr. Judycki earned a B.S. in Civil Engineering from New England
College in Henniker, New Hampshire and a M.S.C.E. with a specialty in
Urban Transportation Planning and Traffic Operations from West Virginia
University. After college in 1968, he joined the FHWA's 18-month
Professional Development Program in Urban Planning. His first permanent
assignment with the FHWA was as the Urban Transportation Planning
Specialist in the California Division Office. In 1994, Mr. Judycki was
selected for the Office of the Secretary of Transportation (OST)
position of Senior Staff Assistant to the Region 5 DOT Secretarial
Representative in Chicago, Illinois. Mr. Judycki's first position in
Washington, D.C., was as the Special Assistant to the FHWA Executive
Director, a position held for five years. He was appointed to the
Senior Executive Service (SES) in 1981 as the Chief of the Urban
Planning & Transportation Management Division. In 1985 he become the
Director of the Office of Traffic Operations before becoming Associate
Administrator for SSA in 1990.
Mr. Judycki is a member of several professional organizations,
including the Institute of Transportation Engineers and the American
Public Works Association. He is the USDOT delegate to the Board of
Directors of the ITS World Congress and the Organization for Economic
Co-operation and Development (DECD)/European Council of Ministers of
Transport (ECMT) Joint Transport Research Bureau and Committee.
Mr. Judycki has been recognized with numerous Senior Executive
Service Annual Performance Awards, the Secretary's Award for
Meritorious Achievement, two team National Partnership for Reinventing
Government (Hammer) Awards, the Lester P. Lamm Memorial Award, the
Secretary of Transportation's Team Award, and the Presidential
Meritorious Senior Executive Rank Award. In 1998, Mr. Judycki received
the Presidential Distinguished Senior Executive Rank Award, the top
honor within the career civil service.
Biography for Benjamin Tang
Mr. Tang is the Principal Bridge Engineer and Team Leader for the
U.S. DOT, Federal Highway Administration (FHWA) at the Office of Bridge
Technology, Washington, D.C. He leads the long span major bridges and
tunnels group. He has served with great distinction as a structural
engineer and program manager in several offices within the FHWA for the
past 30 years.
He is a graduate of University of Maryland (B.S.C.E.) and
University of Illinois (M.S.C.E.). He is a licensed professional
engineer in Maryland and serves on several technical committees on the
Transportation Research Board, AASHTO, State Transportation Agencies
and private industry.
Benjamin is the technical expert and review authority for all
bridge and structural matters for the federal-aid bridge program. He is
responsible for drafting federal polices and regulations. He is also
responsible for developing the bridge technology program under the
SAFETEA-LU. He is championing the use of innovative bridge
technologies, such as accelerated bridge construction, high-performance
materials and load resistance factor design.
Mr. Tang received numerous distinguished service awards and
recognition throughout his federal career. He shared the American
Society of Civil Engineers, 2007 Pankow Award for Innovation in
collaboration with the developer of a cradle system for cable-stayed
bridges.
Mr. Lipinski. [Presiding] Thank you, Mr. Judycki, right
there on time. Next we have Mr. Harry Lee James. Mr. James?
STATEMENT OF MR. HARRY LEE JAMES, DEPUTY EXECUTIVE DIRECTOR AND
CHIEF ENGINEER, MISSISSIPPI DEPARTMENT OF TRANSPORTATION;
MEMBER, STANDING COMMITTEE ON HIGHWAYS, AMERICAN ASSOCIATION OF
STATE HIGHWAY AND TRANSPORTATION OFFICIALS
Mr. James. Thank you, Mr. Chairman, for allowing me to be
here today. Again, I am Harry Lee James. I am the Chief
Engineer for the Mississippi DOT. I am also the former State
Bridge Engineer for the Mississippi Department of
Transportation. On behalf of AASHTO, I would like to thank you
for the focus of this committee on transportation
infrastructure needs and particularly bridges, bridge safety,
and preservation; and hopefully I can provide you with some
information and answers to the questions that you have
previously provided to us.
As far as bridge inspection, the techniques that are used
by the states today range from simple to complex; simple being
the inspector going out, looking at the structure, touching it,
feeling it, listening to it, and to the complex inspections
that require ultrasound, magnetic particle testing, monitoring
devices that have been imbedded in a bridge during its
construction as well. Many times though the basic is the best.
Keep it simple so that we can minimize the inconvenience to the
public, because many times you have to close a bridge or, at
least, some lanes of traffic when you are performing an
inspection, and also for the safety of the bridge inspector as
well. Many times he is precariously dangling hundreds of feet
in the air trying to manage for his own safety as well as a
multitude of equipment that he might have to carry with him to
perform his tasks. Again, basic is best in most cases.
As far as research, there is always a greater need. We need
to continue our efforts to look for the next best thing. We
continue to use proven technologies in our design and our
construction. However, we can't give up the fight for looking
for new technologies out there to help us looking at this aging
infrastructure that we have.
How do we prioritize our bridge repair and replacement
needs at the statewide level? There is no single approach,
there is no magic bullet. We just have to go out there and do
what we can with the resources that we have. It takes much
diligence and stewardship on the part of the DOTs and Federal
Highway to maintain the systems that we have. We are very
fortunate that bridge management systems have been helped in
development by Federal Highway, and many states have adopted
these in their use to look at prioritizing these repair and
replacement programs that we have to do.
As far as consequences of what could happen short-term,
what may happen long-term, the bridges that were designed and
built back in the '30s and up to the '50s, '60s, and even into
the '70s, and we have bridges of many ages on our system of
some 16,000 in the State of Mississippi, those bridges, the
ones particular on the interstates, were designed back in the
'60s are not designed for the loads that they carry today.
Consequently, they deteriorate at a faster level than what was
originally anticipated. As far as long-term, things are not
going to get any better. We can build something today a lot
cheaper than we could build it five years ago with the current
increases of cost of construction and other issues that we have
to deal with as a State highway agency. More is always needed
to assist us.
One thing that could help us is getting projects entered
into our work program at a faster rate. It is unfortunate that
we have to wait until a tragedy such as what happened in
Minnesota. And also in Mississippi, we lost two major bridges
on our coast from Katrina; it takes something like that for us
to basically suspend the rules and be able to act fast to get
something back in service in a timely manner.
It is very challenging, my job, to look at a state-wide
program and maintain it. We have the traveling public that we
have to see to, we have our construction workers, as well as
our contractors, and safety is a big issue.
I really appreciate the opportunity to come before you
today to offer some information to you, and I will be glad to
take any questions that you might have. Thank you.
[The prepared statement of Mr. James follows:]
Prepared Statement of Harry Lee James
Introduction
Mr. Chairman, my name is Harry Lee James. I am the Deputy Executive
Director and Chief Engineer for the Mississippi Department of
Transportation. I am a member of the Standing Committee on Highways of
the American Association of State Highway and Transportation Officials
(AASHTO), and I am a registered Professional Engineer in the State of
Mississippi.
On behalf of AASHTO, I want to express my appreciation for your
focus on infrastructure needs in America. The State Departments of
Transportation (State DOTs) consider bridge safety and bridge
preservation to be one of our highest priorities, and we take this
responsibility to preserve the safety and mobility of the traveling
public very seriously.
I am here to provide you and the public with the answers to some
critical questions that have been posed by the House Committee on
Science and Technology since the tragic collapse of the Interstate 35W
bridge in Minneapolis.
Question 1
A) What technologies and techniques do state departments of
transportation currently use to inspect bridges? What are the benefits
and disadvantages?
Every state conducts a thorough and continual bridge inspection and
rehabilitation program. America's bridges are inspected every two years
by trained and certified bridge inspectors, conditions are carefully
monitored, and, where deterioration is observed, corrective actions are
taken.
The most common and widely used method of inspection is by far the
visual inspections by teams led by Professional Engineers. These can be
described as using Sight, Sound and Touch for General Inspections.
Sight is the normal visual inspection technique used by all states,
Sound refers to the sounding technique (use of hammer sounding and
chain drag) on concrete to integrity of the concrete (does it crumble),
and Touch refers to the 100 percent hands on Fracture Critical Member
inspection included in every General Inspection. If needed, these
inspections are supplemented by other non-destructive testing methods.
The benefit of visual inspections is that we can collect a large
volume of data on the condition of the components of every bridge. The
disadvantage is that inspections are costly and time consuming. In
addition to qualitatively documenting visible damage, degradation, and
distress in structural elements, visual inspection can include
quantitative measurements such as loss of steel due to corrosion or the
size of cracks in concrete.
Some other common Non-Destructive testing (NDT) techniques are
Magnetic Particle method for detection of cracks in suspected areas,
ground penetrating radar to evaluate bridge decks with overlays,
infrared thermography and ultrasonic testing to identify cracks that
are either too small to be seen, or are beneath the surface of the
metal and dye-penetrant tests which also detect cracks that are not
visible to the naked eye. Dye-penetrant tests are inexpensive and very
simple to perform. Mag-particle is fairly easy to perform. The
disadvantages are that dye-penetrant only identifies cracks that have
broken the surface of the steel. Mag-particle testing requires
relatively flat and smooth surfaces. Almost all the common technologies
are applicable to steel, not concrete or timber. All the techniques
require specialized training and often times expensive equipment.
Some other innovative techniques include special ``health
monitoring'' of bridges using special gauges and sensors. Some of these
include strain gauges, inclinometers, load cells, weather stations,
corrosion sensors, humidity sensors, and accelerometers.
Oregon is out front when it comes to using advanced technology to
assess the condition of bridges. Currently they have instruments on
seven bridges and have installed a device that uses air pressure to
measure scour at bridge foundations on one other bridge.
B) What research is needed to improve inspections?
The National Bridge Inspection Standards are periodically reviewed
and updated to reflect the latest knowledge. The last update was
implemented in January 2005. The program was changed significantly in
several areas:
The fracture-critical inspection interval was
shortened (not to exceed 24 months) and the qualifications for
underwater inspectors were increased (80 hours of training are
now required).
The qualification requirements for Program Managers
and Team Leaders were increased. For example, non-licensed
engineers must take a 10-day class and have five years
experience, with most of that experience taking place directly
in field inspection, to become a Team Leader.
States must have a quality control and assurance
program in place for their bridge inspection program. The
program should include periodic field review of inspection
teams, periodic bridge inspection refresher training for
program managers and team leaders, and independent review of
inspection reports and computations.
These recent updates to the National Bridge Inspection Standards
demonstrate that the Federal Highway Administration is diligent in
updating and advancing inspection standards based on input from the
states. In addition, states frequently supplement federal inspection
requirements with more detailed data collection and analysis. For
example, 40 states currently employ an element-level inspection process
that focuses on individual components of a structure.
In an informal AASHTO survey conducted on Sept. 1st to which 27
states and the USDA Forest Service replied, several areas of research
were determined to be high priority. The one most often mentioned was
the need for non-destructive testing technology/equipment that is
inexpensive and easy to operate for a ``typical'' inspector. Also
needed are ways to effectively manage and interpret the immense amount
of data that is produced by bridge monitoring systems. In addition,
with all of the pre-stressed and post-tensioned structures currently
being built, it will be necessary to inspect the strands in these
structures to determine the operating structural capacity of these
bridges after they have been in service and exposed to the environment
for some time. An effective way to inspect this and deterioration of
pretensioned, pre-stressed strands in pre-cast beams and boxes is
needed. Loss of pre-stress concrete capacity can occur rapidly and lead
to collapse such as the I-70 bridge in Pennsylvania.
Additional research in is also needed in ways of yielding cost-
effective, efficient methodologies for the identification and
monitoring of fatigue cracks in steel members. Lastly, many states
would like to see the reinstatement of the HERMES ground penetrating
radar research now tabled at Turner-Fairbank.
C) How is FHWA helping to meet these research needs?
The Federal Highway Administration (FHWA) has been a strong
supporter of bridge research and bridge inspection and evaluation
standards. Due to small staff and limited resources, many local
governments do not have the expertise to use the technologies or review
the research that is generated.
FHWA works cooperatively with the American Association of State
Highway and Transportation Officials (AASHTO) to fund bridge related
research projects through the Transportation Research Board TRB and
National Cooperative Highway Research Projects (NCHRP). They also fund
bridge research projects through SHRP2.
FHWA funds have been used by the states and by AASHTO for software
development projects to perform structural evaluation of existing
bridges and to develop bridge management tools. Most notably, FHWA
funded a pilot project with Caltrans in the early 1990's to develop
bridge management software that contains advanced asset-management
decision-making capabilities. This software is now funded by AASHTO and
is known as PONTIS. It is used nationally and internationally.
FHWA owns and operates the Turner-Fairbank Highway Research Center,
which provides research and development related to new highway
technologies. Current bridge inspection technologies being developed
include ground penetrating radar (Hermes II), acoustic emission
monitoring. Bridge technology programs operated under this research
center include Non-Destructive Evaluation (NDE) Validation Center, the
Long-Term Bridge Performance Program and Paint and Corrosion
Laboratories.
The NDE Validation Center is designed to act as a resource for
state transportation agencies, industry, and academia concerned with
the development and testing of innovative nondestructive evaluation
(NDE) technologies.
The Long-Term Bridge Performance Program (LTBP) was launched
earlier this year. It is 20-year research effort that is strategic in
nature with specific short- and long-term goals. The program will
include detailed inspection, periodic evaluation and testing,
continuous monitoring, and forensic investigation of representative
samples of bridges throughout the United States to capture and document
their performance. We feel this is an important program because it has
the potential to provide a better understanding of bridge deterioration
and to provide better deterioration models than are now used in Pontis.
FHWA sponsors studies to develop inspection techniques and remedies
for common problems found in the Nation's inventory of bridges such as
arresting fatigue cracks, detecting and preventing protecting bridge
with chlorides in concrete, detecting and preventing development of
reactive aggregate.
Recently, the Federal Highway Administration's Transportation
System Preservation program, an initiative of the Asset Management
division, has added Bridge Preservation to the program. Several
workshops have been held in 2007 and these workshops have helped to
identify needed research in the area of bridge preventative
maintenance.
Also, the International Activities office of FHWA has sponsored
several international scan tours in the area of Bridge inspection and
quality control. Most recently, a European Scan was undertaken in June
2007 in the area of Bridge Quality Control and Quality Assurance.
Additionally, FHWA works to help sponsor Transportation Pooled Funds
which support specific research projects Federal Highways also provides
training through the National Highway Institute and helps to
disseminate information through many publications, reports, memos and
announcements.
While substantial funding has been devoted to bridge research,
since the passage of SAFETEA-LU research funding has been constrained.
Two factors give rise to that constraint. First, overall research
funding was less than recommended by AASHTO and second, earmarks
exceeded the total dollars made available for FHWA research and thus
constrained overall discretionary research.
The pending SAFETEA-LU Technical Corrections bill that passed the
House and is pending in the Senate would free up additional funds for
the FHWA research program with no need to increase the overall cost of
SAFETEA-LU. AASHTO has urged passage of this important legislation.
Bridge Research Under SHRP 2
Recent events have again demonstrated that America's highways, once
the envy of the world, are deteriorating, sometimes disastrously so.
Through age and overuse their capacity to safely serve America's
transportation needs is being compromised. The Renewal focus area of
the Second Strategic Highway Research Program (SHRP 2) seeks to develop
the tools needed to systematically ``renew'' our highway infrastructure
to serve the 21st century in ways that are rapid, minimally disruptive
to users, communities, and the environment and that yield much longer-
lived bridges and roadways.
Highway infrastructure largely comprises three basic elements:
bridges, pavements and earthworks. All three elements are showing the
deterioration of age and over-use and all three are addressed in the
SHRP 2 research plans. While all three elements are vulnerable to
deterioration that might compromise the physical safety of highway
users, bridges are, by far, the most vulnerable. This fact was not lost
on the committees of experts that guided the formulation of the SHRP 2
research, and renewal of America's highway bridges remains a key
element of the SHRP 2 research, despite the dramatic reduction in funds
actually authorized in the SAFETEA-LU legislation. Unfortunately, some
of the originally planned research--directly applicable to safety
assessment and the maintenance and repair of existing structures--
proved unaffordable.
Bridge Research Currently Included in SHRP 2
Three current projects, with total funding of $5 million, directly
address bridge renewal, including ``Durable Bridges for Service Life
beyond 100 Years: Innovative Systems, Subsystems, and Components.''
Two other projects, valued at $8 million, address bridge renewal in
part, including one project related to ``A Plan for Developing High-
Speed, Nondestructive Testing Procedures for Both Design Evaluation and
Construction Inspection.''
Bridge Research Included in the Original SHRP 2 Research Plans
TEA-21 called for the Transportation Research Board (TRB) to
conduct a study to determine the goals, purposes, research agenda and
projects, administrative structure, and fiscal needs for a new
strategic highway research program or a similar effort. Among the
recommendations of the committee as detailed in TRB Special Report 260,
was that ``Highway Renewal'' be included as one of the four focus areas
of SHRP 2. A subsequent detailed analysis of highway renewal research
needs alone indicated a funding need of approximately $95 million.
However, the passage of SAFETEA-LU provided only $150 million for
the entire SHRP 2 research effort; thus serious cutbacks were made in
all four research focus areas. Funding available for highway renewal
research was reduced to $30 million. Efforts to optimize the research
plans and combine projects were undertaken. Nonetheless, five important
bridge research projects were dropped from the SHRP 2 program,
including such topics as ``Bridge Repair/Strengthening Systems,''
``Techniques for Retrofitting Bridges with Non-Redundant Structural
Members,'' and ``Monitoring and Design of Structures For Improved
Maintenance and Security.''
These projects would be as valuable to the safety assessment,
maintenance management, and repair of existing bridges as they would be
to a program of systematic renewal. Statements of work have already
been developed for these research projects. The cost estimates shown
are bare minimums and may require some upward adjustment.
TRB is ready to coordinate the SHRP 2 research with any program
pursuing this research. The research remains significant to the
achievement of the overall SHRP 2 goals.
Question 2
A) For those bridges deemed structurally deficient, how do state and
local governments prioritize repairs and replacements?
The states use a number of different methods to prioritize their
bridge needs.
While there is no ``single approach'' to prioritizing bridge
program candidates, all approaches consider safety, then preservation
and serviceability. Many states use a priority type of formula or a
ranking system. These formulas and rankings taking into effect a
combination variables of many different types. Some of the common
considerations, in addition to the structurally condition ratings, are
load ratings, field conditions, available funding, importance
(criticality) of the bridge, average daily traffic, and alternate or
detour route length. In addition to asset management programs and
rankings, projects are scrutinized and approved through the normal STIP
process that includes approvals from State and local transportation
leaders and the transportation commissions where applicable.
One example is Oregon's project selection method. It integrates
inspection data from PONTIS with other bridge condition data,
specifically non-deterioration based needs, including, as examples;
seismic, scour, and functional deficiencies. ODOT links various data
collections to identify projects in twelve categories. Data primarily
from Pontis is used to select problem bridges in the substructure,
superstructure, and deck condition categories. Data outside of Pontis
is used to select problem bridges in the seismic, scour, bridge rail,
deck width, load capacity, vertical clearance, paint, coastal bridge
(cathodic protection), and movable bridge categories.
Many states are moving away from a strictly ``worst first'' project
selection process. Increases in the costs of traffic mobility and
project staging have also influenced the move toward targeting route
segments for repair and replacement projects.
However, several states are also still using a ``worst first''
selection method, sometimes with consideration for traffic load, social
effects and politics. Overall, there is no ``norm'' in the area of
prioritization.
Michigan's Well Developed Bridge Management System
Michigan DOT has a well developed asset management program that
preserves Michigan's bridge through a balanced approach of doing
capital preventive maintenance, rehabilitation, and replacement. They
use a forecasting tool called Bridge Condition Forecast System to
determine the best implementable strategy of the three types of work.
Today the mix of fixes is 18 percent Preventive Maintenance, 30 percent
rehabilitation, and 48 percent replacement.
The department also uses AASHTO CoRe elements and Pontis smart
flags to make project level decisions, track deterioration rate of
bridge elements (transition probabilities). Progress is monitored each
year towards defined condition state goals, and strategy is modified as
needed. By slowing the deterioration rate of fair bridges (keeping them
from becoming structurally deficient (SD) ) and concentrating on
rehabilitating (first option) and replacement of SD bridges, the state
has been able to make good progress at eliminating Structurally
deficient bridges. Local agencies have reengineered their program (once
called critical bridge program, but today called local agency bridge
program), following the lead of the state trunkline program, and they
are now managing their network of local agency structures.
While doing this the state has found the federal regulations
regarding the Highway Bridge Program (HBP) are still too restrictive
(although improving). This has resulted in several states transferring
money out of the HBP program into other less restrictive programs. This
gives a false impression that bridge money is not needed, which is very
misleading. The HBP program is becoming more flexible with the
allowance to use HBP funds for painting bridges and preventive
maintenance, however, it is still built upon the framework of the 30
year old sufficiency rating formula that assigns a rating based upon
structural deficiency and functional obsolescence.
In the latest federal highway legislation, SAFETEA-LU, the name of
the portion of the act providing funding for bridge improvement and
preservation was changed from ``Highway Bridge Rehabilitation and
Replacement Program'' (HBRRP) to ``Highway Bridge Program'' (HBP).
Along with the name change, came increased flexibility for states,
counties, and cities to fund a broader assortment of bridge
preservation projects. For example, ``systematic preventive
maintenance'' now qualifies for HBP funds. With this change, it now
appears that the three broad categories of bridge preservation are
covered; i.e., replacement, rehabilitation and preventive maintenance.
However, there remains at least one important exception that prevents
the HBP program from becoming what it can and should be. As it
currently stands, HBP funds still cannot be used for rehabilitation or
replacement of bridge decks when only the deck is in poor condition.
The reason for this is explained below.
Bridges qualify for rehabilitation and replacement based upon the
``Sufficiency Rating Formula, as explained in Appendix B of the FHWA's
``Recording and Coding Guide for the Structure Inventory and Appraisal
of the Nation's Bridges.'' The sufficiency rating formula is a 100-
point scale. A bridge in new condition, having no deficiencies, has 100
points, and each deficiency on a bridge reduces the structure's
sufficiency rating by a predetermined value. When a bridge's
sufficiency rating falls below 80 points, the bridge qualifies for
rehabilitation, and when the sufficiency rating falls below 50 points,
the bridge qualifies for replacement.
The problem, as it relates to bridge decks, is the formula gives
very little weight to the condition of a bridge deck. The formula only
lowers a bridge's sufficiency rating three points when the deck
condition (NBI Item #58) is four (poor). It only lowers the sufficiency
rating five points when the deck condition is three (serious) or below.
In comparison, the formula lowers a Bridge's sufficiency rating 25
points when, either, the superstructure (NBI Item #59) or the
substructure (NBI Item #60) conditions are four (poor). The formula
lowers a bridge's sufficiency rating 40 points, and 55 points, when the
condition of the superstructure or substructure is three (serious) or
two (critical), respectively. As a result, if only a bridge deck is
rated poor, the bridge does not qualify for HBP funds.
To qualify preventive maintenance activities for HBP funds, states
must work with their FHWA division office to demonstrate they have a
``systematic plan'' for maintaining their bridges. Once a ``systematic
plan'' is demonstrated, a list of HBP eligible preventive maintenance
activities can be developed. In Michigan, preventive maintenance
activities relating to bridge decks include deck patching, expansion
joint replacement, epoxy overlays, and hot mix asphalt overlays. Rigid
overlays (i.e. * concrete, latex modified concrete, or micro-silica
concrete) are classified as rehabilitation projects, therefore a bridge
must meet the more stringent sufficiency ratings as discussed above.
Rigid overlays are a well-proven cost effective preservation
activity for bridge decks, especially those that receive large traffic
volumes. Likewise, it is easily shown that it is cost effective to
rehabilitate or replace structurally deficient bridge decks before more
extensive damage is done to the superstructure and substructure. It
simply does not make sense to exclude rehabilitation and replacement of
bridges decks from HBP funds when the rest of the structure is in fair
to good condition. This is like saying you should not replace or repair
the shingles on your home's roof until moisture has been allowed to
penetrate and destroy the drywall or crack the foundation.
By definition, a bridge is ``structurally deficient'' if any one of
the three major elements is rated four (poor) or below. Consequently,
if only the bridge deck is rated four (poor) or below, the bridge is
structurally deficient. This is an important point to be aware of
because Section 1114 of SAFETEA-LU ``declares that it is in the vital
interest of the United States that a highway bridge program be carried
out to enable States to improve the condition of their highway bridges
over waterways, other topographical barriers, other highways, and
railroads through replacement and rehabilitation of bridges that the
States and the Secretary determine are structurally deficient or
functionally obsolete and through systematic preventative maintenance
of bridges''. Therefore, allowing rehabilitation or replacement of
structurally deficient bridge decks is consistent and directly
supported by SAFETEA-LU.
It is also important that to remember and convey that bridges do
not exist in a vacuum. Bridges are always tied to the roads they
connect. Many of the structurally deficient bridges we have are located
on major freeways that are tied up in long-term corridor improvement
studies, or there simply is not enough money to do the needed
improvement to the corridor or interchange. The bridge may need
replacement, but that must go along with a freeway widening (adding
lanes), or redesign of an interchange. In many cases, we can not just
simply fix the bridges without doing major road improvements also.
Bridge Management Software
Currently, 43 states plus Puerto Rico and the District of Columbia,
along with several local agencies (including Los Angeles and Phoenix)
and six international agencies, use an AASHTO BRIDGEWare software
program called Pontis. This is a computer-based bridge management
system developed to assist in the challenging task of managing an
agency's structures. Pontis can store bridge inventory and inspection
data, formulate network-wide preservation and improvement policies for
use in evaluating the needs of each bridge in a network, and make
recommendations for what projects to include in an agency's capital
plan for deriving the maximum benefit from limited funds.
Once inspection data have been entered, Pontis can be used for
maintenance tracking and federal reporting. Pontis integrates the
objectives of public safety and risk reduction, user convenience, and
preservation of investment to produce budgetary, maintenance, and
program policies. Additionally, it provides a systematic procedure for
the allocation of resources to the preservation and improvement of the
bridges in a network. Pontis accomplishes this by considering both the
costs and benefits of maintenance policies versus investments in
improvements or replacements.
Responses from an informal August 2007 AASHTO survey11
found that 17 of 37 states use an in-house computerized bridge
management system that allows for prioritization and monitoring of
elements in conjunction with either Pontis data collection or an in-
house database. In some cases, Pontis is used by the states as a data
collection system only, but many states are also using the management
capabilities of Pontis, which allow them to predict bridge element
deterioration levels and prioritize spending.
As noted, most states have some form of computerized bridge
management system in place; however, the complexity and abilities vary.
The goal of this effort may be to better define the abilities a state
should have within its bridge management system and allow for
flexibility within each state to accomplish these goals in the most
efficient manner possible.
B) What are the possible short- and long-term consequences of
maintaining the current level of bridge repair and replacement efforts
(if no changes are made to the current systems)?
Most states responding to the AASHTO informal survey cite that
their systems will not be affected greatly in the short-term if there
are no changes made. However, most stated that long-term effects of an
unchanging system would be significant. One example can be seen in
Utah, where approximately five percent of the State system is
Structurally Deficient. UDOT has developed and maintains strategic
goals and performance measures for the overall health of its bridge
system, as do many other states. Historically, funding from the Federal
Bridge Programs (HPRR) is not adequate to address all of the needs.
Therefore Utah's program is supplemented with State funds for both
bridge replacement and preventive programs. Even with the supplemental
State funds, resources are not adequate to address all of the
Structurally Deficient bridges.
The consequence of inadequate funding includes increased risk.
Typically states manage the risk of structurally deficient bridges with
a variety of processes including; more frequent inspections, and
consideration for load restrictions, shoring, and possible closure of a
bridge. There are a large number of bridges that were built during the
``Interstate Era.'' Many of these bridges are already functionally
obsolete, and many more will become functionally obsolete as traffic
volumes increase. More importantly, the volume of freight is expected
to double in the next 20 years, and the long-term trend in the industry
has been for increased vehicle weight and axle loads. Improvements in
tire technology will allow even greater axle loads, and the expanded
use of drop axles has resulted in vehicles with concentrated loading
that far exceeds the standard vehicles used for load rating.
There has been insufficient funding to replace bridges at a
sustainable rate. If the funding is maintained at current levels, this
trend will continue and the average bridge age will continue to
increase, while the conditions continue to decrease. Bridges will
deteriorate faster than they can be repaired and/or replaced. This will
require load limiting (posting) of bridges and/or the closing of
bridges. Thus limiting the use of the existing transportation system--
significantly impacting the Nation's economy.
A funding program is needed that will allow states to ``sustain''
an efficient transportation system for the distant future. Since
bridges have a 50 to 100 year lifespan, the results of a non-
sustainable funding program are not immediately apparent, but will
nonetheless result in significant impacts to the economy if not dealt
with at a level that will ``sustain'' the efficiency needed for
economic growth.
Some states report that, in the short-term, failure to maintain SD
bridges will necessitate costly ``emergency'' repairs to allow routes
to remain open at required functional levels. These emergency repairs
reduce funds available for more permanent and cost effective
rehabilitations
Is Current Bridge Investment Adequate?
It should be noted that currently states are spending dramatically
more money on bridges than is provided under the federal Bridge
Program. For example, in 2004 the federal Highway Bridge Program
provided $5.1 billion to the states. That year, states actually spent
$6.6 billion in federal aid for bridge rehabilitation. State and local
funding added another $3.9 billion for bridge repairs. FHWA reports
that in 2004 a total of $10.5 billion was invested in bridge
improvements by all levels of government.
Oregon's 10-year state bonding program is providing $1.3 billion of
state funding for the rehabilitation of hundreds of deficient bridges.
This is twice the amount received in federal bridge funding.
According to U.S. DOT's 2006 Conditions and Performance Report, the
backlog of needed repairs on National Highway System bridges alone
total over $32 billion, which includes over $19 billion needed on
Interstate Highway System bridges. Structurally deficient bridges on
the National Highway System only represent one-tenth of the total
number of structurally deficient bridges on the U.S. road network. As
wear and tear on our nation's infrastructure continues, it will only
continue to increase the needs in coming years.
The Conditions and Performance report also states that maintaining
the current investment level of $10.5 billion annually would reduce the
backlog of bridge needs by half over the next 20 years. An increase in
that investment level to $12.4 billion per year for bridge system
rehabilitation would eliminate the backlog by 2024, excluding any kind
of necessary spending on expansion or enhancements.
In addition to providing needed additional funding, we recommend
investigating what can be done to streamline processes that delay the
implementation of needed repairs on our nation's highway system,
including reducing environmental red tape and allowing the use of
proprietary engineering-related products that could spur innovation in
long-term solutions.
During the last reauthorization of the federal transportation bill,
SAFETEA-LU gradually increased annual funding levels for the Highway
Bridge Program by six percent over the life of the bill (from FY 2005
to FY 2009). However, far outpacing that increased funding have been
dramatic increases in materials costs for steel, concrete, fuel,
asphalt. States report that prices jumped 46 percent over the years
from 2003-2006. In addition, the Conditions and Performance report
attributes increases in the ``cost to maintain highways'' to the rising
cost of construction in large urbanized areas due to environmental
mitigation and construction strategies (such as night work) intended to
reduce the impacts of work zones on users.
Aside from the well-documented dramatic increases in construction
costs, there have been equally dramatic increases in traffic,
especially heavy trucks, on the Nation's major highways. Today, the
average mile of Interstate highway carries 10,500 trucks per day. By
2035, that number is expected to more than double to 22,700 trucks per
day.
The truck issue also extends to overweight vehicles. As an example,
in Iowa, the DOT's Bridge Office issues an average of 50 permits per
day for trucks weighing over 156,000 pounds, or approximately 7,500
permits per year. These trucks are roughly twice the standard ``legal''
weight limit, causing significant wear and tear on the system, but are
necessary for the economic health of our country. And these numbers are
only anticipated to increase.
Thus, we are left with a system that has challenges to meet, and a
program that does not have enough funding to overcome the current
backlog.
Question 3
A) How do State and local governments use the results of research and
technology development by the Federal Government?
Many states work closely with the FHWA, AASHTO, and other groups to
share technology with local government agencies and consultants. In
addition, training programs such as the National Highway Institute,
Library sessions, and Webinar's, are used to exchange information.
Similar to any field, advances in highway infrastructure typically are
the result of cumulative improvements over time from many sources
instead of major breakthroughs. The Departments of Defense, Energy,
Commerce, and Transportation all contributed to the state-of-the-art in
structural steels, corrosion-resistant materials, Portland cement
concrete, and asphaltic concrete that are now routinely used for
highways. In addition to the materials, designs, and practice that are
currently in use, reports and research papers stemming from Federal
Government programs are routinely referenced by practitioners and
researchers at State and local DOTs to make decisions on using a new
technology or pursuing further research into a new technology.
There are many excellent reports that are produced through the
National Cooperative Highway Research Program, under the direction of
the Transportation Research Board of the National Academies. These
reports let states know what the leaders in certain areas are doing.
Taking the time to read reports and learn about what others have done
enables individual states to avoid the expense and time of learning the
lessons that have already been learned by others. For example, the
NCHRP ``Manual for Bridge Rating Through Load Testing'' has excellent
guidance for bridge owners to test older bridges that have low
calculated load capacity yet are not deteriorated and seem to be
performing well.
The results of many federal research projects are used to implement
changes to design philosophies and inspection techniques. Recent
examples include the migration of our design philosophy to LRFD, the
addition of new SU type rating vehicles to the current federal rating
vehicles (Type 3, 3S2, 3-3), etc. States use the results of research
from sources such as NCHRP for the inspection, testing and analysis of
bridges, when the results of the projects are directly implemented into
the AASHTO bridge design, maintenance and analysis codes or when the
results of the research is published.
In addition, most states enroll DOT staff in National Highway
Institute (NHI) courses for technical training. NHI courses are
developed with the help of Federal Government and participate in
federally sponsored conference and workshops to seek information on new
technologies.
B) How do federal technology transfer programs for bridge-related
research and technology development help the states?
Technology transfer programs, such as organizing conferences and
NHI courses, assist states in being aware of the current state-of-the-
practice. Peer exchange programs help peers to meet and discuss best
practices and issues they face every day. The states encourage FHWA to
develop periodic bridge inspection/management peer exchange programs
and program peer reviews to facilitate more discussions and
improvements.
The Technology Transfer (T2) program, National Highway Institute,
and other program are extremely helpful in sharing information. The T2
program is very beneficial in that it has a dedicated staff to
administer the program, reducing workload for DOT and FHWA personnel.
More information on T2 can be found at: http://www.federallabs.org/.
The Federal Laboratory Consortium for Technology Transfer (FLC) is the
nationwide network of federal laboratories that provides the forum to
develop strategies and opportunities for linking laboratory mission
technologies and expertise with the marketplace. The FLC was organized
in 1974 and formally chartered by the Federal Technology Transfer Act
of 1986 to promote and strengthen technology transfer nationwide.
Today, more than 250 federal laboratories and centers and their parent
departments and agencies are FLC members.
In many federally sponsored technology transfer events, individuals
with many years of experience are able to share what technology had
worked for them, and what technology had fallen short. This was an
excellent forum to learn about the research being done on a recently
developed paint that holds promise for a significantly longer service
life. Without technology transfer programs, individual states would not
benefit from the lessons of others and would have to rely exclusively
on vendor information. One example of these types of events were two
Bridge Preservation Workshops held earlier this year. These workshops
enabled engineers from all states to gather together and discuss issues
related to bridge management and maintenance.
In addition, technology transfer and programs such as the
Innovative Bridge Research and Deployment Program (IBRD) provide a
means to disseminate information, experience and ``lessons learned''
that allow states to use new materials such as high strength steel and
high performance concrete more efficiently. More information on IBRD
can be found at: http://www.fhwa.dot.gov/bridge/ibrd/
C) What technical assistance have state and local governments received
from the U.S. DOT for steel truss bridge inspections following the
bridge collapse in Minneapolis? Was this technical assistance helpful?
Since August 1, in compliance with federal requests, every state
has reviewed or is in the process of re-inspecting its steel deck truss
bridges.
Most states noted that although their FHWA division office let them
know they were available to assist, no assistance from them was needed
or solicited. However, several states noted and appreciated the
numerous forms of technical assistance provided by FHWA ranging from
Technical Advisories, copies of reports, updates on emergency efforts,
national teleconferences, and meetings with the local FHWA office. A
few states also noted that the technical advisories did provide a basis
for a uniform national response in light of the I-35 collapse in
Minnesota.
In Georgia, it was noted that the FHWA Division participated in the
inspections of GDOT's two steel deck truss bridge structures and GDOT
appreciated their participation in the inspections.
Conclusion
We continue to make progress in addressing bridge replacement and
rehabilitation needs, but there just isn't enough money to close the
gap. Each year, as bridges continue to age and deteriorate, it is an
uphill battle to keep up with the demands.
AASHTO and the State DOTs stand ready to help Congress address the
needs for transportation infrastructure in America. The tragic
Minneapolis bridge collapse rightly raises concerns about the condition
and needs of the Nation's bridges. AASHTO and the State DOTs continue
to work with NTSB and others as they investigate the cause of this
tragic event, and when a cause has been identified we are committed to
working jointly with Congress to address the issue head-on and to
correct the situation in the most expedient way possible. Until that
time, it is important to avoid premature speculations, and diligently
obtain all relevant data to arrive at the appropriate solution.
Biography for Harry Lee James
After having earned a Bachelor of Science Degree in Civil
Engineering (with honors) from Mississippi State University (MSU) in
1976, Harry Lee James worked in the private construction industry and
later for a consulting engineering firm before joining the MDOT team as
a bridge designer in 1982. Mr. James was appointed State Bridge
Engineer in 1999, and in February 2003 he was appointed to the position
of Deputy Executive Director/Chief Engineer. Because of his focus on
bridges throughout his career, this appointment has given Mr. James the
unique opportunity and obligation to promote better and safer bridges.
Mr. James is a licensed Professional Engineer and a licensed
Professional Land Surveyor in Mississippi. He serves on the American
Association of State Highway Officials' (AASHTO) Standing Committee on
Highways, he is a member of the National Cooperative Highway Research
Program (NCHRP) 12-62 Panel, and he was formerly on the AASHTO
Subcommittee on Bridges and Structures. Mr. James serves as vice chair
of the AASHTO Standing Committee on TRAC and is the committee's newest
member. Mr. James believes that top-down support of TRAC, or any
program is key to its success, and he plans to bring that message to
the states within his southeast U.S. AASHTO district.
Mr. James is a native of Canton, Mississippi. He is the father of
two young children, both girls. Together with his wife, who is also an
engineer, they hope to inspire their children to careers in
transportation.
Mr. Lipinski. Thank you, Mr. James. I feel right at home
here with all the engineers on the panel. Dr. Womack?
STATEMENT OF DR. KEVIN C. WOMACK, DIRECTOR, UTAH TRANSPORTATION
CENTER; PROFESSOR OF CIVIL AND ENVIRONMENTAL ENGINEERING, UTAH
STATE UNIVERSITY
Dr. Womack. Thank you. I am here as the Chair of the
Transportation Policy Committee of the American Society of
Civil Engineers, but I am also a structural engineer by
training and have been involved in the area of bridge research
for the past 15 years. I am pleased to lend ASCE's expertise to
the problem of the Nation's crumbling infrastructure that was
highlighted by the collapse of the I-35 West bridge in
Minneapolis.
Like all bridges, all man-made structures deteriorate.
Deferred maintenance allows deterioration and causes bridges to
be more susceptible to failure. As with other critical
infrastructure, a significant increase in investment is
essential to maintain the benefits and to assure the safety
that society demands. Research is a critical effort that can
reduce the existing investment gap between the funding
available and the funding needed to improve the condition and
performance of our highway infrastructure.
The Highway Trust Fund has been an essential source of
funding for surface transportation research and technology and
SAFETEA-LU, the Surface Transportation Research, Deployment and
Development and the University Transportation Research sections
were both completely programmed or earmarked and over-
authorized creating a difficult environment within which FHWA
and RITA must allocate funds. An added result to this fact is
that FHWA now has no discretionary funds to maintain certain
core research programs, which means that its Turner-Fairbank
Highway Research Laboratories are underutilized, its contract
research program is limited, and such critical efforts such as
the biennial Conditions and Performance Report may be in
jeopardy. The practice of extreme programming and earmarking of
the research title needs to be eliminated in future
transportation authorization bills.
When looking at research in bridges, the current university
and FHWA research activities do look at materials and process.
Newer, more efficient designs can now be made due to computer
analyses, which have been researched extensively. Design
methods, the newest of which is the Load and Resistance Factor
Design, have been researched and must continue to be researched
to determine the performance of these lighter structures that
use materials more efficiently.
There is a need to study long-term bridge life to develop a
better understanding of how bridges age and deteriorate. This
will allow us to better predict and model bridge behavior and
could lead to improved maintenance practices and better bridge
management. The FHWA's Long-Term Bridge Performance Program, a
planned 20-year research program, should lead the way in this
effort.
Obviously, to maintain bridges, more funds are needed, and
more of those funds need to go into the maintenance of the
structure, not just the deck. It is our hope that the Long-Term
Bridge Performance Program will help to provide answers as to
how to properly channel our nation's bridge maintenance funds.
Once a bridge is safely and optimally designed, it is of
most use to the public if it can be built quickly and with the
least disruption to traffic. Accelerated bridge construction
can help to accomplish this goal. Prefabrication of bridge
elements and new construction techniques are being championed
by states and the Federal Highway Administration. However,
performance questions remain, particularly in the area of
seismic performance of these types of structures. Research into
these types of questions is essential.
In terms of safety, inspection is the crux of this issue. A
more clearly defined inspection protocol should be developed
through research that goes beyond visual inspections to testing
and monitoring that includes instrumentation. This new protocol
must be as objective as possible with no doubt as to what steps
are to be taken and when. One way to make visual inspection
less subjective is to have it done by licensed, professional
engineers and not by technicians. This, however, will lead to
an exacerbation of the workforce issue and the current shortage
of civil engineers, particularly in the transportation area.
The objective of research is to develop beneficial new
technologies that will be better performing and more durable.
Though the initial cost of these new technologies may be
higher, their efficiencies and durability will, in the long
run, reduce maintenance, repair, and rehabilitation costs in
addition to creating longer service lives. This is how research
can assist in closing the current investment gap that is so
well-defined in the Conditions and Performance Report. The
Federal Government should do more to encourage states to use
new technologies without requiring the states to assume all the
risk. There is an FHWA program, the Innovative Bridge Research
and Deployment Program, that is designed to provide money to
states for the use of innovating materials or technologies.
This program needs to be expanded and monitored to ensure that
these funds actually go toward proving new technologies.
However, at the end of the day, procurement and procedures must
be changed to count for life cycle costs, innovation, and
contractor qualifications, or there will be no motivation to
use new technologies. Successfully and efficiently addressing
the Nation's infrastructure issue, bridges and highways
included, will require long-term, comprehensive, nationwide
strategy, one that includes research. For the safety and
security of our families, we as a nation can no longer afford
to ignore this growing program. We must demand leadership from
our elected officials because without action, aging
infrastructure represents a growing threat to public health,
safety, and welfare, as well as to the economic well-being of
our nation.
Thank you, Mr. Chairman, that concludes my statement. I
will be glad to answer any questions the Committee would have.
[The prepared statement of Dr. Womack follows:]
Prepared Statement of Kevin C. Womack
Chairman Gordon, Congressman Hall and Members of the Committee:
Good morning. I am Kevin Womack, Chair of the Transportation Policy
Committee of the American Society of Civil Engineers (ASCE).\1\ I am a
Professor of Civil and Environmental Engineering at Utah State
University and Director of the Utah Transportation Center, a federally
funded University Transportation Center. I serve on the National
Academies' Research and Technology Coordinating Committee, an advisory
committee to the Federal Highway Administration. I am a structural
engineer by training and have been involved in the area of bridge
research for the past 15 years.
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\1\ ASCE, founded in 1852, is the country's oldest national civil
engineering organization. It represents more than 140,000 civil
engineers in private practice, government, industry, and academia who
are dedicated to the advancement of the science and profession of civil
engineering. ASCE is a 501(c) (3) non-profit educational and
professional society.
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Thank you for holding this hearing. As someone who has worked in
this field for many years, I can say that there are few infrastructure
issues of greater importance to Americans today than bridge safety.
I am pleased to appear today to lend ASCE's expertise to the
problem of the Nation's crumbling infrastructure that was highlighted
by the tragic events of August 1, 2007, when the I-35W Bridge in
Minneapolis collapsed into the Mississippi River.
I. Bridge Conditions
More than four million vehicles cross bridges in the United States
every day and, like all man-made structures, bridges deteriorate.
Deferred maintenance accelerates deterioration, which may make bridges
more susceptible to failure. As with other critical infrastructure, a
significant investment is essential to maintain the benefits and to
assure the safety that society demands.
In 2005, ASCE issued the latest in a series of assessments of the
Nation's infrastructure. Our 2005 Report Card for America's
Infrastructure found that as of 2003, 27.1 percent or 160,570 of the
Nation's 590,753 bridges were structurally deficient or functionally
obsolete, an improvement from 28.5 percent in 2000. In fact, over the
past 12 years, the number of deficient bridges, both structurally
deficient and functionally obsolete categories, has steadily declined
from 34.6 percent in 1992 to 25.8 percent in 2006.
However, this improvement is contrasted with the fact that one in
three urban bridges (31.2 percent or 43,189) were classified as
structurally deficient or functionally obsolete, much higher than the
national average.
In 2005, the FHWA estimated that it would cost $9.4 billion a year
for 20 years to eliminate all bridge deficiencies. In 2007, FHWA
estimated that $65 billion could be invested immediately in a cost
beneficial manner to address existing bridge deficiencies.
The 10-year improvement rate from 1994 to 2004 was a 5.8 percent
(32.5 percent - 26.7 percent) reduction in the number of deficient
bridges. Projecting this rate forward from 2004 would require 46 years
to remove all deficient bridges. Unfortunately, bridges are now
deteriorating at a rate faster than we can maintain them, so this 46
year projection has grown to 57 years to eliminate all deficient
bridges. This shows that progress has been made in the past in removing
deficient bridges, but our progress is now slipping or leveling off.
There is clearly a demonstrated need to invest additional resources
in our nation's bridges. However, deficient bridges are not the sole
problem with our nation's infrastructure. The U.S. has significant
infrastructure needs throughout the transportation sector including
roads, public transportation, airports, ports, and waterways. As a
nation, we must begin to address the larger issues surrounding our
infrastructure so that public safety and the economy will not suffer.
II. Bridge Inspection Program
The National Bridge Inspection Standards (NBIS), in place since the
early 1970s, require biennial safety inspections for bridges in excess
of 20 feet in total length located on public roads. These inspections
are to be performed by qualified inspectors. Structures with advanced
deterioration or other conditions warranting closer monitoring are to
be inspected more frequently. Certain types of structures in very good
condition may receive an exemption from the two-year inspection cycle.
These structures may be inspected once every four years. Qualification
for this extended inspection cycle is reevaluated depending on the
conditions of the bridge. Approximately 83 percent of bridges are
inspected once every two years, 12 percent are inspected annually, and
five percent are inspected on a four-year cycle.
Information is collected documenting the conditions and composition
of the structures. Baseline composition information is collected
describing the functional characteristics, descriptions and location
information, geometric data, ownership and maintenance
responsibilities, and other information. This information permits
characterization of the system of bridges on a national level and
permits classification of the bridges. Safety, the primary purpose of
the program, is ensured through periodic hands-on inspections and
ratings of the primary components of the bridge, such as the deck,
superstructure, and substructure. This classification and condition
information is warehoused in the National Bridge Inventory (NBI)
database maintained by FHWA. This database represents the most
comprehensive source of information on bridges throughout the United
States.
It is important to note, however, that the value of the NBI is
limited, although it is certainly a useful tool to evaluate the
condition of public bridges. Among its limitations, a user cannot tell
the condition of a specific element of the bridge, i.e., a girder or
diaphragm or bearing. The overall rating encompasses the
superstructure, the substructure, and the deck which all have unique
elements. Therefore, the NBI cannot offer the kind of information that
may be required for in-depth analysis.
Two documents, the American Association of State Highway and
Transportation Officials' (AASHTO) Manual for Condition Evaluation of
Bridges and the FHWA's Recording and Coding Guide for the Structure
Inventory and Appraisal of the Nation's Bridges, provide guidelines for
rating and documenting the condition and general attributes of bridges
and define the scope of bridge inspections. Standard condition
evaluations are documented for individual bridge components as well as
ratings for the functional aspects of the bridge. These ratings are
weighted and combined into an overall Sufficiency Rating for the bridge
on a 0-100 scale. These ratings can be used to make general
observations on the condition of a bridge or an inventory of bridges.
The factors considered in determining a sufficiency rating are:
S1--Structural Adequacy and Safety (55 percent maximum), S2--
Serviceability and Functional Obsolescence (30 percent maximum), S3--
Essentiality for Public Use (15 percent maximum), and S4--Special
Reductions (detour length, traffic safety features, and structure
type--13 percent maximum).
In addition to the sufficiency rating, these documents provide the
following criteria to define a bridge as structurally deficient or
functionally obsolete, which triggers the need for remedial action. The
structural capacity of a bridge is also determined and is used to
decide if a bridge should be restricted to trucks of lower weights.
Structurally Deficient--A structurally deficient bridge may be
restricted to light vehicles because of its deteriorated structural
components. While not necessarily unsafe, these bridges usually have
limits for speed and weight, and are approaching the condition where
replacement or rehabilitation will be necessary. A bridge is
structurally deficient if its deck, superstructure, or substructure is
rated less than or equal to 4 (poor) or if the overall structure
evaluation for load capacity or waterway adequacy is less than or equal
to 2 (critical). This is on a condition scale with ratings between 9
(excellent) and 0 (representing a failed condition). In a worse case
scenario, a structurally deficient bridge may be closed to all traffic.
Functionally Obsolete--A bridge that is functionally obsolete is safe
to carry traffic but has less than the desirable geometric conditions
required by current standards. A bridge is functionally obsolete if the
deck geometry, under-clearances, approach roadway alignment, overall
structural evaluation for load capacity, or waterway adequacy is rated
less than or equal to 3 (serious). A functionally obsolete bridge has
older design features and may not safely accommodate current traffic
volumes and vehicle sizes. These restrictions not only contribute to
traffic congestion, but also pose such major inconveniences as lengthy
detours for school buses or emergency vehicles.
Structural Capacity--Components of bridges are structurally load-rated
at inventory and operating levels of capacity. The inventory rating
level generally corresponds to the design level loads but reflects the
present bridge and material conditions with regard to deterioration and
loss of section. Load ratings based on the inventory level allow
comparisons with the capacities for new structures. The inventory level
results in a live load which can safely utilize an existing structure
for an indefinite period of time. The operating rating level generally
describes the maximum permissible live load to which the bridge may be
subjected. This is intended to tie into permits for infrequent passage
of overweight vehicles. Allowing unlimited numbers of vehicles to use a
bridge at the operating level may shorten the life of the bridge.
Bridge Engineers and Bridge Inspectors:
Bridge inspection services should not be considered a commodity.
Currently, NBIS regulations do not require bridge inspectors to be
Professional Engineers, but do require individuals responsible for load
rating the bridges to be Professional Engineers. ASCE believes that
non-licensed bridge inspectors and technicians may be used for routine
inspection procedures and records, but the pre-inspection evaluation,
the actual inspection, ratings, and condition evaluations should be
performed by licensed Professional Engineers experienced in bridge
design and inspection. They should know the load paths, critical
members, fatigue prone details, and past potential areas of distress in
the particular type of structure being inspected. They must evaluate
not only the condition of individual bridge components, but how the
components fit into and affect the load paths of the entire structure.
The bridge engineer may have to make immediate decisions to close a
lane, close an entire bridge, or take trucks off a bridge to protect
the public safety.
A new inspection protocol must be developed. This will involve
visual inspection, load testing, and monitoring through instrumentation
of bridges. The new protocol must be as objective as possible, with no
doubt as to what steps are to be taken and when. One way to make the
visual inspection less subjective is to have them all done by licensed
professional engineers and not by technicians. This, however, will lead
to an exacerbation of the workforce issue and the current shortage of
civil engineers, particularly in the transportation arena, that is only
going to get worse.
III. Bridge Design and Research
The Highway Trust Fund has been an essential source of funding for
surface transportation research and technology (R&T) for decades.
Research results have led to many benefits including: materials that
improve the performance and durability of pavements and structures;
design methods that reduce scour (and the consequent threat of
collapse) of bridges; intelligent transportation systems technologies
that improve safety and reduce travel delay; methods and materials that
radically improve our ability to keep roads safely open in severe
winter weather; innovative management approaches that save time and
money; and analytical and design approaches that reduce environmental
impacts, support sustainable development and improve the aesthetic and
cultural aspects of transportation facilities.
These benefits are provided through several major transportation
research programs. In the highway area these programs include the FHWA
program, the National Cooperative Highway Research Program (NCHRP), and
State department of transportation programs largely funded through
State Planning and Research (SPR) funds. In the transit area the main
programs are that of the Federal Transit Administration (FTA) and the
Transit Cooperative Research Program (TCRP). The University
Transportation Centers (UTC) program supports various transportation
modes.
In SAFETEA-LU, the Surface Transportation Research, Deployment and
Development and the University Transportation Research sections were
both completely programmed or earmarked and over-authorized, creating a
difficult environment within which FHWA and the Research and Innovative
Technology Administration (RITA) must allocate funds. An added result
to this practice is that FHWA now has no discretionary funds to
maintain certain core research programs, which means that its Turner-
Fairbank Highway Research Center laboratories are underutilized. The
Research Center's contract research program is limited, as is its
provision of expert technical support for states when they encounter
bridge and tunnel problems. States are now made to prove they can pay
for any FHWA technical support. Finally, such critical efforts as the
biennial Conditions and Performance Report may be in jeopardy. The
practice of extreme programming and earmarking of the research title
needs to be eliminated in future surface transportation authorization
bills. Competition and selection on qualifications, not special
interest group influence is essential for an effective research
program. And the FHWA must be left with sufficient discretionary funds
to maintain certain core programs.
When looking at research on bridges, the current university and
FHWA research agenda does look at materials and process. While
materials and process are areas for improvement, the design of bridges
is a well-developed discipline. In fact, one reason the bridges in this
country have lasted so long is that those 30-, 40-, and 50-year-old, or
even older bridges were typically designed very conservatively with
appropriate redundancy. Newer more efficient designs can now be made
due to computer analyses (finite elements), improved materials, and
construction advances, which have been researched extensively. Design
methods, the newest of which is the Load and Resistance Factor Design
(LRFD) have been researched and must continue to be researched to
determine the performance of these lighter structures that use
materials more efficiently.
Better performing concretes can be made with increased durability
and, if needed, increased strength. Evaluation of this concrete with
new, high strength reinforcing bars is needed, as well as research into
the engineering properties and feasibility of using lightweight high
performance concrete for bridges.
Research is ongoing at NCHRP to evaluate the remaining fatigue life
of existing older steel bridges in America. This is an important study.
However we also need to continue the research, development, and
deployment of high performance steel for bridges, with its increased
toughness and improved weldability.
Fiber-reinforced polymer (FRP) composites continue to hold promise
for the future for bridges. Research to develop guidelines for using
FRP in bridge decks, as well as using FRP externally-bonded sheets as a
strengthening repair system for concrete girders and piers, is
important.
Bridge and tunnel security is an area that demands our attention.
Research into blast resistant design for bridges and tunnels and
development of specifications and training materials for bridge
engineers is important to our nation's security.
Hurricane Katrina is most known to engineers for the damage that it
did to New Orleans and the levees. What isn't as well known is the
damage that it did to bridges in Louisiana, Mississippi, and Alabama
due to wave action, storm surge, and debris. Research being done
through a joint AASHTO-FHWA-TRB transportation pooled-fund study to
develop Guide Specification and a Handbook of Retrofit Options for
Bridges Vulnerable to Coastal Storms is critical work for the safety
and operability of our nation's bridges during extreme events.
There is also a need to study long-term bridge life to develop a
better understanding of how bridges age and deteriorate. This will
allow us to better predict and model bridge behavior and could lead to
improved maintenance practices and better bridge management. The FHWA's
Long-Term Bridge Performance Program, a planned 20-year research
program, should lead the way in this effort. At present, this program
is significantly under-funded.
As for maintenance, it is based on the funding available and which
bridge is most in need of repair. That usually means deck repair, not
the structure of the bridge. When the public notices problems, such as
potholes and the like, these get attention. The public rarely notices
severe structural problems unless concrete is falling from the bottom
of an overpass bridge.
Obviously, to properly maintain bridges, more funds are needed, and
more of those funds need to go into the maintenance of the structure,
not just the deck. It is our hope that the Long-Term Bridge Performance
Program will help to provide answers as to how to properly channel our
nation's bridge maintenance funds.
Once the bridge is safely and optimally designed, it is of most use
to the public if it can be built quickly and with the least disruption
to traffic. Accelerated bridge construction can help to accomplish this
goal. Prefabrication of bridge elements and new construction techniques
are being championed by states and the Federal Highway Administration.
However, some questions remain concerning performance in earthquake
regions. Research into these questions is needed.
In short, how bridges are designed, withstand extreme events, age,
and how construction techniques and materials for bridges can improve
should continue to be researched to look for more efficient practices.
In terms of safety, inspection is the crux of this issue. I firmly
believe that a more rigorous inspection and testing protocol should be
developed and this should be a significant research topic. This is
where an issue arises with the I-35W bridge. It was inspected
appropriately, issues were discovered, and then there were no strict
guidelines as to what to do next. It was decided to more closely
monitor and inspect the bridge, but that was all done visually. If a
better defined protocol were developed, the next step should have been
instrumentation that could have been permanently placed on the bridge
to monitor its condition constantly. The chances that instrumentation
would have picked up something critical in Minneapolis would have been
much greater than further visual inspections alone. Whether or not this
would have picked up the impending failure is something we cannot know,
but chances would have definitely been better.
A more clearly defined inspection protocol should be developed,
through research, which goes beyond visual inspections to include
testing and monitoring with instrumentation.
Few states or their bridge contractors take advantage of new
technologies due to the current practice of selecting low-cost bids.
There usually is no incentive for the contractors to use new
technology; it is often more expensive and may have increased risk.
Until life cycle costs, along with the consideration of innovative
materials or construction practices, are considered in awarding bids,
then nothing is going to happen. States are very wary of using new
materials and technologies, because if the technology does not work,
the state becomes legally liable.
The Federal Government should do more to allow states to use new
technologies, without requiring the states to assume all the risk.
There is an FHWA program--the Innovative Bridge Research and Deployment
program, with a funding level of $13.1 million available--that is
designed to provide money to states for the use of innovative material
or technologies. However, I do not believe the funds are being used by
all the states in a manner that would result in proof of new
technologies.
Again, until procurement procedures are changed to account for life
cycle costs, innovation, and contractor qualifications, there is little
motivation or financial incentive to be innovative.
IV. Addressing the Current Bridge Deficiencies
We need to adopt a risk-management approach to determine our
priorities for the maintenance, rehabilitation and replacement of
bridges. We must define the greatest risk, looking at the likelihood of
bridge failure and the cost in lives and money of such a failure. We
must then determine where the funds should go to ensure the greatest
return in terms of public safety. This means that the bridges in the
worst shape do not necessarily get the money for repairs if they have a
low potential loss of life and economic impact. With limited funds,
this is the most fiscally most responsible way to go.
The short-term consequences are what we have seen occur-periodic
bridge failures that result in loss of life and economic loss. The
long-term consequences of doing nothing more than we do now will be
potentially disastrous. As the classic bridges (unique designs that
span major rivers) become older and the Interstate bridges reach the
end of their design life, bridge collapses may become more frequent
with time, as will the resulting loss of life, and the economic
consequences of tying up the country's major shipping lanes.
V. ASCE's Policies Regarding Bridges
In 1988, the National Council on Public Works Improvement estimated
that a doubling of the annual expenditure on infrastructure is needed
to meet national needs. Doubling of spending, even through the use of
innovative financing techniques, is unlikely. To increase productivity
and reduce costs through the development of innovative design,
materials, construction methodologies, rehabilitation technologies,
maintenance procedures, and operation techniques are essential, to
reducing the correct investment gap that exists in caring for our
surface transportation infrastructure.
Currently, there are a number of obstacles which discourage
innovation on a widespread scale. Civil engineers, for example, are
under increasing pressure to eschew innovation and to be conservative
in their judgment because of lawsuits, rules, regulations, legislation,
standards, budget expectations and restrictions, and a desire for
financial predictability.
Fragmentation of the design and construction industry limits the
support of long-term research efforts that could result in
technological gains and innovation. Appropriate technical innovation
and support groups can contribute to improved disaster resilience, cost
effectiveness and improved productivity and quality throughout the
infrastructure industry.
The public demands that the operation, maintenance, expansion,
rehabilitation and new construction of the Nation's infrastructure be
performed to enhance economic vitality, disaster resilience and public
safety, but with minimal impact on their lives. The public requirement
calls for innovative solutions to minimize costs of delays,
environmental costs and project costs. Establishing these innovative
solutions requires coordination and sustained research and development.
INFRASTRUCTURE RESEARCH AND INNOVATION
ASCE supports efforts to foster research and development related to
infrastructure facilities. The goal is to enhance support of economic
vitality while assuring public safety and disaster resilience through
increased innovation, productivity and security in design, materials,
construction, rehabilitation, maintenance and operations as applied to
America's infrastructure facilities.
ASCE believes appropriate methods to implement infrastructure
research, innovation and security include:
Supporting legislation and policies that encourage
development of new technology and processes;
Supporting and encouraging, through appropriate
incentives, research to accelerate the development of existing
technology and develop new technology in the fields of design,
materials, construction, maintenance, rehabilitation, and
operation of the infrastructure with understanding of the need
for disaster resilience;
Supporting appropriate funding for infrastructure
research at the federal level in conjunction with State/local
agencies, universities and private enterprise;
Supporting efforts to identify and disseminate
information on Federal, State, and local governments, academia
and private sector infrastructure research and development
activities;
Supporting efforts to limit the risk and liability
that would discourage innovative infrastructure technology;
Focusing national attention on infrastructure needs
through cooperative efforts;
Providing opportunities for academia and practicing
engineers to conduct research and development activities; and
Supporting efforts that develop and implement new
strategies and technologies to mitigate the impact of disasters
on the Nation's infrastructure in a consistent manner.
The Role of the Federal Government in Civil Engineering Research and
Development
Federal R&D funding currently provides a substantial percent of the
total U.S. civilian R&D investment. Federal leadership is essential to
civil engineering research. With inadequate federal funding, the
ability to maximize the leveraging of R&D funds through government-
university-industry partnerships would not be possible.
ASCE supports a focused federal civil engineering research and
development (R&D) program consistent with national goals. Programs
should promote new U.S. capabilities, improve efficiencies and advance
the practice of civil engineering to improve the quality of life.
ASCE encourages coordinated and integrated basic and applied civil
engineering research that leverages federal R&D funds through
government-university-industry partnerships. Programs fostering basic
research should focus on maintaining a steady flow of talent and
technology to U.S. industry and agencies. Programs focusing on higher
risk research with the potential for high payoff should meet national
needs and improve the quality of life by:
Enhancing public health and safety;
Enhancing environmental quality;
Supporting the goals of sustainable development;
Improving public works infrastructure;
Improving global competitiveness in U.S. civil
engineering products and processes; and
Enhancing national security.
SURFACE TRANSPORTATION RESEARCH FUNDING
ASCE supports the following general principles in the
reauthorization of research and technology programs in the Nation's
surface transportation legislation:
Improvements resulting from research and technology
(R&T) are critical to achieving national transportation goals
in safety, quality of life, economic health, environmental
impacts, sustainability, and security.
Adequate funding should be dedicated to R&T
activities.
Research programs should be conducted according to
the highest scientific and engineering standards, from
priority-setting to award of contracts and grants to review and
evaluation of research results for implementation.
Research programs should be carried out with
appropriate involvement from stakeholders in the public,
private, and academic sectors.
Technology transfer activities are critical to
successful implementation of research results and should be
supported with R&T funds.
Public-private partnerships should be fostered by
identifying appropriate roles for each partner and providing
incentives for private investment.
Within the context of the general principles set out above, ASCE
supports the following actions regarding specific surface
transportation R&T programs.
The research and technology portion of the State
Planning and Research (SPR) program should be maintained to
help support state-specific activities while continuing to
encourage the states to pool these resources to address matters
of more general concern.
University research should continue to be supported
through the University Transportation Centers (UTC) program
using a competitive selection process that guarantees quality
participants and fairness in the allocation of funds. The
Federal Highway Administration's (FHWA) program should be
strengthened by giving it sufficient funding and flexibility to
implement the recommendations of TRB Special Report 261, The
Federal Role in Highway Research and Technology: to focus on
fundamental, long-term research; to perform research on
emerging national issues and on areas not addressed by others;
to engage stakeholders more consistently in their program; and
to employ open competition, merit review, and systematic
evaluation of outcomes.
A continuation of the Strategic Highway Research
Program SHRP II beyond the life of SAFETEA-LU, ensuring that
critical research will be continued in key areas of surface
transportation.
The Federal Transit Administration's (FTA) research
program should be given sufficient funding and flexibility to
work with its stakeholders to develop and pursue national
transit research priorities.
The new Research and Innovative Technology
Administration (RITA) should have a well-defined scope and
responsibility and appropriate funding, in addition to
currently authorized research funding, so that it may
supplement and support the R&T programs of the modal
administrations.
VI. Conclusion
Successfully and efficiently addressing the Nation's infrastructure
issues, bridges and highways included, will require a long-term,
comprehensive nationwide strategy--one that includes research and
identifying potential financing methods and investment requirements.
For the safety and security of our families, we, as a nation, can no
longer afford to ignore this growing problem. We must demand leadership
from our elected officials, because without action, aging
infrastructure represents a growing threat to public health, safety,
and welfare, as well as to the economic well-being of our nation.
Thank you, Mr. Chairman. That concludes my statement. I would be
pleased to answer any questions that you may have.
Biography for Kevin C. Womack
Dr. Womack is currently Professor of Civil and Environmental
Engineering at Utah State University, and Director of the Utah
Transportation Center, a Federally funded University Transportation
Center.
Dr. Womack received his Doctorate degree in Civil Engineering from
Oregon State University in 1989, his Masters of Science degree from the
University of Pennsylvania in 1985 and his Bachelors of Science degree
from Oregon State University in 1980. He has been a member of the
American Society of Civil Engineers for over 20 years and currently
chairs their National Transportation Policy Committee. He has also
served as a past Chair of the Technical Committee on Structural
Identification and Health Monitoring of Constructed Facilities; and as
a member of the Technical Committee on the Performance of Structures
During Construction.
Currently Dr. Womack is also serving on the National Academy's
Research and Technology Coordinating Committee, an advisory committee
to the Federal Highway Administration.
In 2001-02 Dr. Womack worked as an AAAS/ASCE Congressional Fellow
for the Senate Committee on the Environment and Public Works, under
then Chairman Senator James Jeffords. He was responsible for writing
much of the research title contained in the Senate version of SAFETEA.
Dr. Womack is a registered professional engineer in the States of
Oregon and Utah, and has worked as a consulting engineer with the firm
of Kramer, Chin and Mayo, Inc. of Seattle, Washington. He is a
structural engineer by training and has been involved in the area of
bridge research for the past 15 years.
Mr. Lipinski. Thank you, Dr. Womack. I can tell you are all
engineers because you are all almost sticking within the five-
minute limit which we don't always see.
Mr. Bernhardt.
STATEMENT OF MR. MARK E. BERNHARDT, DIRECTOR, FACILITY
INSPECTION, BURGESS & NIPLE, INC.
Mr. Bernhardt. Thank you. Mr. Chairman, honorable Members
of the Science and Technology Committee, good morning.
Again, my name is Mark Bernhardt, and I am the Director of
Facility Inspection for Burgess & Niple in Columbus, Ohio. I
have been working in the bridge inspection field for over 10
years, and in that time I have managed, reviewed, or performed
more than 3,000 bridge inspections.
Burgess & Niple is also a member of ACEC, the American
Council of Engineering Companies. ACEC is the business
association of America's engineering industry representing over
5,500 member firms from across the country. On behalf of ACEC
and the industry, we appreciate the opportunity to testify
before you today to discuss the research and technology that
contributes to bridge safety.
In order for transportation agencies to make sound
decisions regarding bridge maintenance and rehabilitation, they
require comprehensive information on bridge conditions. Many
factors control the validity of the data being supplied to the
decision-makers. These factors are as varied as inspector
training and experience, effective of bridge management
systems, inspection methods, and available funding. All of
these factors play a role in ensuring bridge safety.
Bridge inspections in the U.S. are generally visual, thus
qualitative in nature. A comprehensive study of the reliability
of visual inspection was performed by the FHWA's Non-
Destructive Evaluation Center in 2001. This study suggested
that visual-only inspections provide data that is often highly
variable and influenced by many factors such as the inspector's
comfort level with working at height, structure accessibility,
and duration of inspection. It is the general consensus within
the engineering community that visual inspection practices must
be supported by rigorous training, certification, and quality
assurance programs and frequently supplemented with testing
techniques to ensure reliable results.
The primary non-destructive evaluation techniques utilized
during the inspection of steel bridges include magnetic
particle, dye penetrant, and ultrasonics. These tests are
relatively low cost, and proven protocols have been developed
for their use and the interpretation of results. For concrete
bridge decks, very simple procedures such as dragging a chain
across the bridge deck can be a very good indication of hidden
deficiencies. Its modern counterpart, ground penetrating radar,
can do the same thing only more objectively and with
repeatability. The Bridge Inspector's Reference Manual which
forms the basis of bridge inspector training programs
nationwide details these test methods as well as dozens of
other effective methods.
What these tests and visual inspection all have in common
is that they record conditions only at a single point in time.
They are a mere snapshot of bridge conditions. While this is
generally adequate for relatively low-risk structures,
structurally deficient or complex structures that pose a
greater risk to the traveling public require more. The emerging
field of structure health monitoring holds much promise for
real-time evaluation of structures and objective evaluation of
bridge conditions. Structure health monitoring involves the
installation of sensors under bridge components that allow for
remote collection and observation of data at any time. These
can include strain gauges, weigh-in motion systems, fiber
optics, cameras, corrosion sensors, and acoustic emission
equipment, all tied to data servers and digitally accessible in
real time.
Funding for research and pilot projects in this area should
continue to be a priority. Bridge engineers can be most
effective by providing the decision-makers in transportation
agencies with objective, data-driven recommendations. This
data, combined with operational risk-based factors, can be used
to determine optimum prioritization of bridge repairs.
Underlying all of this, however, is the fact that simply
collecting more data and providing more frequent inspections
will not improve overall bridge safety. Additional funding for
bridge repair and replacement is required to adequately keep
pace with bridge program needs.
Professional engineers benefit greatly from the results of
research and technology programs funded by the Federal
Government. The traveling public is the greatest beneficiary,
however. Lessons learned and the conclusions reached during
NCHRP and FHWA research projects are effectively disseminated
to practicing bridge engineers. They are immediately
incorporated into improved design, evaluation, and analysis
methods.
In the weeks following the Minnesota I-35 bridge collapse,
Burgess & Niple was asked by a number of State transportation
agencies to assist with the inspection of steel deck truss
bridges. This work was performed in response to an FHWA
Technical Advisory. In general, the inspections were carried
out in the same manner as those completed prior to the I-35
collapse. Investigation into the I-35 bridge collapse is still
ongoing. It will likely be some time before the investigating
engineers reach a definitive conclusion as to the precise cause
of the collapse. Even if the cause of the collapse is found to
be unrelated to bridge inspection practices, it is my hope that
the dialog that has resulted from this tragic event will lead
to improvements in the field of bridge inspection and result in
a safer infrastructure system. A better understanding of bridge
conditions through the expanded use of testing and structure
health monitoring can help to improve both the allocation of
bridge repair funds and bridge safety.
Thank you, Mr. Chairman, and I am happy to answer any
questions you or the Committee Members may have.
[The prepared statement of Mr. Bernhardt follows:]
Prepared Statement of Mark E. Bernhardt
Mr. Chairman, honorable Members of the Science and Technology
Committee, good morning.
My name is Mark Bernhardt and I am the Director of Facility
Inspection for Burgess & Niple, Inc. in Columbus, Ohio. I have been
working in the bridge inspection field for over 10 years and in that
time I have managed, reviewed, or performed more than 3,000 bridge
inspections and 160 load ratings.
Burgess & Niple is also a member of ACEC, the American Council of
Engineering Companies, the business association of America's
engineering industry representing over 5,500 member firms across the
country. On behalf of ACEC and the industry, we appreciate the
opportunity to testify before you today to discuss the research and
technology that contributes to bridge safety.
Bridge deterioration is a significant problem facing transportation
agencies nationwide. This is evidenced by the more than 73,000
structurally deficient bridges currently listed in the National Bridge
Inventory (NBI). In order for federal, State, and local agencies to
make sound decisions regarding bridge maintenance, rehabilitation, and
replacement programs, they require comprehensive information on bridge
conditions. Many factors control the validity of the data being
supplied to the decision-makers in transportation agencies. These
factors are as varied as inspector training and experience;
effectiveness of bridge management systems; inspection methods; and
available funding. All of these factors play a role in ensuring bridge
safety. In today's testimony, I will focus my comments on just one of
these areas--inspection methods. Specifically, I will outline some
common techniques and technologies employed during bridge inspection
operations, the emerging field of Structure Health Monitoring, and the
effectiveness of technology transfer programs.
BRIDGE INSPECTION TECHNIQUES
Bridge inspections in the U.S. are generally visual, thus
qualitative in nature, and follow the requirements outlined in the
National Bridge Inspection Standards. Bridge inspections are performed
to determine if any immediate hazards exist that would warrant reducing
allowable loads on a structure or closing it entirely; to ascertain the
extent of deficiencies or structural damage resulting from
deterioration or other causes; and to enable bridge maintenance,
repair, or replacement to be programmed effectively through early
detection of deficiencies.
The primary tool employed by bridge inspectors today is the eyes. A
comprehensive study of the reliability of visual inspection was
performed by the FHWA's Non-Destructive Evaluation Center in 2001. This
study suggested that visual-only inspections provide data that is often
highly variable and influenced by many factors such as the inspector's
comfort level with working at height, structure accessibility, and
duration of inspection. With regard to localized defects in
superstructure members, the study found that less than 8% of the
inspectors successfully located weld cracks and other implanted defects
in test bridges. It is the general consensus within the engineering
community that visual inspection practices must be supported by
rigorous training, certification and quality assurance programs, and
supplemented with testing techniques to ensure reliable results.
Many common and proven non-destructive and destructive testing
techniques are available to the inspector to supplement visual
observations and provide more useful quantitative data. Additionally,
the emerging field of Structure Health Monitoring holds much promise
for real-time evaluation of structures and objective evaluation of
bridge conditions. Providing more quantitative data to bridge program
managers enables them to more effectively allocate bridge
rehabilitation dollars. One current challenge with these tests,
however, is how to best integrate the results into existing Bridge
Management Systems.
The primary nondestructive evaluation techniques utilized during
the inspection of steel bridges include magnetic particle, dye
penetrant, and ultrasonics. These tests are relatively low cost, and
proven protocols have been developed for their use and the
interpretation of results. For concrete bridge decks, very simple
procedures such as dragging a chain across a bridge deck can be a very
good indication of hidden deficiencies. Its modern counterpart, Ground
Penetrating Radar, can do the same thing, only much more objectively
and with repeatability. Electrical potential can be measured to assess
corrosion of embedded reinforcing steel, samples of concrete can be
extracted for laboratory testing, and Impact Echo tests can be used to
locate voids in post-tensioning ducts. The Bridge Inspector's Reference
Manual, which forms the basis of bridge inspector training programs
nationwide, details these test methods as well as dozens of other
effective methods.
LIMITATIONS OF CURRENT PRACTICES
What these tests all have in common, as well as the federally
mandated NBI inspections, is that they are often used to record
conditions only at a single point in time. They are a mere a snapshot
of bridge conditions. While this is generally adequate for relatively
low risk structures, structurally deficient or complex structures that
pose a greater risk to the traveling public require more. This is where
Structure Health Monitoring holds the most promise. Structure Health
Monitoring involves the installation of various sensors and monitors
onto bridge components that allow for remote collection and observation
of data at anytime. These can include strain gages, weigh-in-motion
systems, fiber optics, cameras, corrosion sensors, and acoustic
emission equipment, all tied to data servers and digitally accessible
in real time. While a number of successful structure monitoring
programs have been implemented, the technology is still emerging.
Funding for research and ``pilot projects'' in this area should
continue to be a priority. Bridge engineers can be most effective by
providing the decision-makers in transportation agencies with
objective, data driven recommendations. The structural condition data,
combined with operational ``risk-based'' factors such as traffic
counts, can be used to determine optimum prioritization of bridge
repairs.
Underlying all of this, however, is the fact that simply collecting
more data and providing more frequent inspections will not improve
overall bridge safety. The engineering and scientific community can
help to improve the relevance of the data by further researching
advanced testing techniques. Additional funding for bridge repair and
replacement is required to adequately keep pace with bridge program
needs.
FHWA LONG-TERM BRIDGE PERFORMANCE PROGRAM
Presently, the FHWA is in the process of rolling out its Long-Term
Bridge Performance Program. This proposed 20-year program will provide
the funding and opportunity to develop standard protocols for the
myriad of nondestructive testing methods, sensors, and monitoring
systems available. The engineering community requires more knowledge in
the areas of life cycle costs, deterioration models and mechanisms, and
validation of the effectiveness of repair and rehabilitation strategies
to improve the practice of bridge management. Another goal of this
long-term program is to provide such data. I would encourage the
Members of Congress to continue funding this essential program when its
budget comes up for renewal.
FEDERAL TECHNOLOGY TRANSFER
Professional Engineers benefit greatly from the results of research
and technology programs funded by the Federal Government. The traveling
public is the greatest beneficiary, however. Lessons learned and
conclusions reached during NCHRP and FHWA research projects are
effectively disseminated to practicing bridge engineers. They are
immediately incorporated into improved design, evaluation and analysis
methods.
In the weeks following the Minnesota I-35 bridge collapse, Burgess
& Niple was asked by a number of State transportation agencies to
assist with the inspection of steel deck truss bridges. This work was
performed in response to FHWA Technical Advisory 5140.27--Immediate
Inspection of Deck Truss Bridges Containing Fracture Critical Members.
In general, the inspections were carried out in the same manner as
those completed prior to the I-35 collapse. Some additional focus was
placed on the gusset plate connections between members due to
speculation that this was an area of concern on the I-35 bridge.
The investigation into the I-35 bridge collapse is still ongoing.
It will likely be some time before the investigating engineers reach a
definitive conclusion as to the precise cause of the collapse. Even if
the cause of the collapse is found to be unrelated to bridge inspection
practices, it is my hope that the dialogue that has resulted from this
tragic event will lead to improvements in the field of bridge
inspection and result in a safer and improved infrastructure system. A
better understanding of bridge conditions through expanded use of
testing and Structure Health Monitoring can help to improve both the
allocation of bridge repair funds and bridge safety.
Thank you Mr. Chairman and I am happy to answer any questions you
or the Committee Members may have.
Biography for Mark E. Bernhardt
Education
Purdue University--BS, Civil Engineering, 1991
Registration
Professional Engineer--Alaska, Arizona, Colorado, Louisiana, Montana,
New York, Ohio, Texas, Utah, Virginia
Summary
Mr. Bernhardt joined Burgess & Niple in 1997 and is Director of the
Facility Inspection Section. In his present position he manages a staff
of engineers who perform structural condition assessments of bridges,
towers, dams, and buildings. Before joining B&N, Mr. Bernhardt gained
experience performing forensic structural inspections of various
facilities nationwide. His professional work experience includes the
following:
Project management of large structural inspection
projects
Bridge inspection and load rating analysis
Quality control/quality assurance reviews
Performance of condition assessments of existing
structures
Structural evaluations in the wake of natural
disasters such as fires, rock slides, hurricanes, and
earthquakes
Use of high-angle rope access techniques to inspect
large buildings, dams, towers, and bridges
Determination of the cause of structural failure
Design of repairs for distressed and deteriorated
structures
He has managed, reviewed, or performed more than 3,000 bridge
inspections and 160 load ratings and climbed more than 100 bridges.
Many of these inspections have utilized both destructive and non-
destructive testing techniques to evaluate conditions. Mr. Bernhardt
has authored a number of papers on bridge inspection and is a qualified
NBI Team Leader experienced with AASHTO and FHWA inspection manuals,
PONTIS, and the use of computer equipment and software for inspection
and load rating. He is also a member of Ohio's FEMA Urban Search and
Rescue Team in the position of Structural Specialist. Mr. Bernhardt
holds a Bachelor of Science degree in Civil Engineering from Purdue
University and is a Registered Professional Engineer in 10 states.
Relevant Background
Bridge Inspection--Project Manager, QA/QC Manager, NBI Team Leader, or
team member on various bridge inspection projects, including a variety
of bridge superstructure types such as arch, girder, suspension, and
truss and involving various materials including steel, concrete, and
timber. Mr. Bernhardt has accessed more than 100 large bridges by
utilizing adapted rock climbing techniques. Representative bridge
inspection projects include:
FHWA Eastern Federal Lands Highway Division Federal
Lands and National Parks Bridge Inspections, Nationwide--
Project Manager for task orders that included NBI inspections
of more than 600 bridges located in Yellowstone National Park,
the Blue Ridge Parkway, the Natchez Trace Parkway, and Golden
Gate National Park and other Federal Lands.
Statewide Bridge Inspections, Arizona--Quality
Control Engineer and Project Manager for multiple projects that
have included more than 1,000 NBI inspections, 160 bridge load
ratings using GT-Strudl and VIRTIS, and development of
rehabilitation plans for more than 20 bridges.
Bronx-Whitestone Bridge, New York, New York--Team
Leader for NBI inspection of the floor system of this major
suspension bridge utilizing adapted rock climbing techniques.
Brooklyn Bridge, New York, New York--Project Manager
for installation of accelerometers and other equipment on the
bridge using industrial rope access techniques as part of a
seismic study of the bridge.
Statewide Fracture Critical Inspections, Alaska--
Fracture critical inspections of 30+ steel truss and arch
bridges located throughout the state. NBI Team Leader and
project Quality Control Engineer. Access to the structures was
gained by the use of adapted rock climbing techniques.
Local Agency Bridge Inspections, Oregon--NBI Team
Leader and Quality Control Engineer for Local Agency NBI
inspection projects completed in Oregon that have included more
than 1,500 bridges of a variety of sizes and materials.
Peace Bridge, Buffalo, New York/Fort Erie, Ontario,
Canada--Quality Control Engineer for the NBI inspection of this
multinational bridge. Inspection reports completed for the
NYSDOT, Peace Bridge Authority, and Ontario Transportation
Ministry.
Concrete Bridge Deck Evaluations, Montana--Performed
detailed condition assessments that included chloride ion
sampling, concrete coring and compression testing, half cell
testing, and chain drag surveys for 14 interstate bridges.
Concrete Bridge Deck Evaluations, Arizona--Performed
detailed condition assessments that included chloride ion
sampling, concrete coring and compression testing, half cell
testing, ground penetrating radar, and chain drag surveys for
133 bridges located throughout the state.
Monroe Street Bridge, Spokane, Washington--Performed
detailed condition assessment of this historic concrete arch
bridge in conjunction with an extensive bridge rehabilitation
project.
Dames Point Cable Stay Inspection, Jacksonville,
Florida--Performed the first ever, detailed hands-on condition
assessment of the steel stay cables using adapted rock climbing
techniques.
Hope Memorial Bridge, Cleveland, Ohio--NBI Team
Leader on inspection of steel truss bridge.
Robert O. Norris Jr. Bridge, Williamstown, Virginia--
NBI Team Leader on inspection of steel truss bridge.
Structural Collapse/Disaster Response--Performed structural condition
assessments and structural safety inspections in the aftermath of
fires, hurricanes, earthquakes, and other incidents. He is a Structural
Specialist on the Department of Homeland Security's FEMA Urban Search &
Rescue Team for the State of Ohio.
Hurricane Katrina, Gulf Coast--Deployed to Gulfport
and Pass Christian, MS, in the aftermath of hurricane to
perform structural assessments of damaged buildings in
conjunction with search and rescue operations. The USAR team
searched more than 2,500 structures.
Hurricane Andrew, South Florida--Evaluated structural
damage at 100+ office buildings, warehouses, apartment
complexes, homes, etc., and determined the scope of required
repairs for damaged buildings. Also involved in a research
study for an insurance company that identified the parameters
which had a significant effect on the performance of
residential structures subjected to hurricane force winds.
Deer Island Tunnel, Boston, Massachusetts--Deployed
to construction site in Boston Harbor following fire in a
tunnel access shaft. Sewage outfall tunnel was being bored 300
feet beneath harbor. Performed post-fire safety inspection of
access shaft and tunnel. Developed debris removal plan and
supervised remediation efforts to ensure that the areas were
safe for construction operations to resume.
Northridge Earthquake, Northridge, California--
Performed structural evaluations of buildings damaged by
earthquake. Developed repair scopes and cost estimates.
Post-Earthquake Evaluation of Tanana River Bridge,
Tok, Alaska--Deployed immediately following earthquake to
perform structural safely evaluation of 1,000-foot truss bridge
located on the Alaskan Highway. Industrial rope access
techniques were used to achieve hands-on inspection of all
portions of structure and avoid the need for heavy mechanical
access equipment on the bridge.
Taco Cabana Roof Collapse, Las Vegas, Nevada--
Performed forensic structural investigation following roof
collapse in restaurant on opening night.
Structural Condition Assessment--Performed condition assessments of
existing structures, evaluation of building materials, assessment of
integrity of building systems, determination of the cause of failures,
and design of repairs for distressed and deteriorated structures. Used
computer programs to aid in the analysis of complex structural systems.
Some notable projects and structures investigated and assessed include:
Peterson v. Mission Viejo Corporation, Highlands
Ranch, Colorado--Evaluated foundation and slab movements for a
builder involved in a class-action lawsuit. Over 1,000 single-
family homes were involved in the suit. Developed a database to
manage and analyze the data collected during inspection and
survey work performed on approximately 200 of the homes.
Developed foundation repair plans for the homes requiring
repairs.
Soldier Field, Chicago, Illinois--Performed a
structural condition assessment of the stadium as part of a
periodic monitoring program at the facility.
Miller Park Baseball Stadium, Milwaukee, Wisconsin--
Condition assessment of steel roof superstructure connections.
Heritage Villas, Laughlin, Nevada--Condition
assessment of walls and roofs at 90+ unit condominium complex.
Rhodes Tower, Cleveland, Ohio--Performed a condition
assessment of the pre-cast concrete facade on 20-story
building. Investigated moisture infiltration problems and used
industrial rope access techniques to inspect the facade.
Westin Hotel, Kansas City, Missouri--Performed a
condition assessment of specific components of the hotel
complex and a structural analysis of a concrete canopy.
Executive Tower Inn, Denver, Colorado--Investigation
of masonry facade on 30-story building and structural analysis
and rehabilitation of concrete floor slabs.
Hyatt Regency Tech Center, Denver, Colorado--
Investigation of foundation movements. Developed parking garage
rehabilitation details.
Various Facilities--Performed condition assessments
and structural analysis of components or entire buildings at
the following facilities:
- North Star Steel--Youngstown, Ohio
- Jefferson at Greenwood Apartment Complex--Greenwood
Village, Colorado
- Super Saver Cinema--Denver, Colorado
- Westminster City Hall--Westminster, Colorado
- Barton Fieldhouse--Cornell University, Ithaca, New
York
- Proctor & Gamble 6th Street Parking Garage--
Cincinnati, Ohio
- Northview Shopping Center--Westminster, Colorado
- Rainbow Shoppes--Westminster, Colorado
- Renaissance Apartments--Los Angeles, California
- Idlewild Condominiums--Reno, Nevada
- Westwood Westside Apartments--Iowa City, Iowa
- Metro Dade County Administration Building--Miami,
Florida
- Cedar Cove Condominium Complex--Aurora, Colorado
- Cherry Creek Towers--Denver, Colorado
- Northside Assembly of God Church--Colorado Springs,
Colorado
- Mt. Carmel West Medical Center Parking Garages--
Columbus, Ohio
Material Testing--Experience evaluating and testing a wide range of
structural building materials including reinforced and pre-stressed
concrete, masonry, steel, and timber. Has utilized both destructive and
nondestructive testing techniques including the following:
Magnetic Particle Testing
Impact Echo
Ultrasonic Testing
Concrete Coring
Sampling for Chloride Ion in Concrete
Dye (Liquid) Penetrant Testing
Ground Penetrating Radar
Half-Cell Potential Measurements in Concrete
Timber Boring
Ground Penetrating Radar
Training
Technical Rescue Awareness--Washington State Homeland Security
Institute, 2007
Bridge Inspection Training--FHWA/NHI/Alaska Department of
Transportation, 2006
Haz Mat First Responder Operations Level Training--Environmental
Options, 2006
IS-200 Basic Incident Command System (I-200 for Federal Disaster)--
FEMA/US Fire Administration, 2005
IS-700 National Incident Management System (NIMS)--FEMA/US Fire
Administration, 2005
Swiftwater/Surface Water Rescue--Ohio Region III Rescue Strike Team,
2005
WMD Terrorism Awareness for Emergency Responders--National Emergency
Response & Rescue Training Center, 2005
Urban Search & Rescue Structures Specialist Training--FEMA/USACOE, 2004
Weapons of Mass Destruction Response Operations--FEMA/US Fire
Administration, 2004
IS-100 Introduction to the Incident Command System (I-100 for Federal
Disaster Workers)--FEMA/US Fire Administration, 2004
Cold Regions Engineering--University of Alaska/University of
Washington, 2003
Effective Bridge Rehabilitation--University of Wisconsin, 1999
NDT Techniques (Dye Penetrant, Magnetic Particle, Ultrasonics)
Training--Staveley Schools, 1998
Bridgeview Bridge Inspection Software Training--Oregon Department of
Transportation, 1998
Confined Space Entry Training, 1997
Bridge Climbing/Industrial Rope Access Training--Burgess & Niple,
Limited, 1997
Seismic Design Using the NEHRP Recommended Provisions--Structural
Engineers Association of Colorado, 1995
Wood Construction Seminar--Wood Products Council, 1993
Concrete Repair Basics Seminar--Rocky Mountain Chapter ACI, 1992
Papers and Presentations
``Hurricane Katrina--Assessment of Structural Damage During FEMA USAR
Operations,'' Water One, Wilmington, Ohio, October 2005.
``Post-Earthquake Evaluation of Tanana River Bridge at Tok, Alaska,''
International Bridge Conference, Pittsburgh, Pennsylvania, June
2003.
``Scanning the Spans,'' Arizona Roads & Streets Conference, Tucson,
Arizona, April 2003.
``The Evolution of Bridge Inspection Techniques & Tools,''
Transportation Systems Center 2000 Workshop, San Antonio,
Texas, February 2000, and Ohio Transportation Engineering
Conference, Columbus, Ohio, 2001.
``Statewide Bridge Deck Survey Using Ground Penetrating Radar,''
Structural Materials Technology IV--An NDT Conference, Atlantic
City, New Jersey, 2000.
``Non-Destructive Testing of Bridge Decks Using Ground Penetrating
Radar,'' Midwest Bridge Maintenance Working Group, Ft.
Mitchell, Kentucky, 2000.
``Condition Assessment of Arizona's Concrete Bridge Decks,'' Western
Bridge Engineers' Seminar, Seattle, Washington, October 1999.
``Bridge Inspection and Rehabilitation,'' Arizona Public Works
Association/Arizona Society of Professional Engineers, 1999
Statewide Conference, Flagstaff, Arizona, August 1999.
``In-Depth Inspection of Arizona's Steel Bridges,'' Arizona Department
of Transportation 1998 Transportation Conference and Expo,
Phoenix, Arizona, 1998, and TRB International Bridge Management
Conference, Denver, Colorado, 1999.
``Forensic Engineering,'' ASCE Student Chapter--Colorado School of
Mines, Golden, Colorado, 1996.
Discussion
Mr. Wu. [Presiding] Thank you very much, Mr. Bernhardt. The
witnesses and everyone in the room have been witness to what
frequently goes on here. The Chairman has had to step away to
introduce his bill in another committee. I apologize to the
witnesses. I have two other committee hearings going on right
now and had to step away quickly to cast a vote, and my
apologies, but I hope I haven't missed too much of the context
of your spoken statements and from your written statements. And
at this point, we enter into the question phase, and the
Chairman recognizes himself for five minutes.
Mr. Bernhardt, you talked about a number of different
testing methods, and some of the other witnesses referred to
them also in their written testimony. Non-destructive testing
has been commonplace in other industries, for example, in
aviation for quite some time. And Mr. Judycki and Mr. Tang,
your research center has worked on many of these testing
methods, and yet bridge inspection continues to be primarily a
visual process. Can you discuss for us what some of the
barriers to adoption are and not just in terms of cost but also
some of the non-cost barriers to adoption? And Mr. Bernhardt,
why don't we begin with you, and then we will start at the
other end of the table for anyone else who has some input on
this.
Mr. Bernhardt. That is an excellent question. I think some
of the primary barriers would be related to just the reluctance
to change. I think sometimes within human nature there is
always a reluctance to change, and people want to stick with
what they are comfortable with and don't want to try new
testing methods and techniques; and I think that is part of it.
Additionally, I think any time a new testing technique is
rolled out and introduced, there has to be an infrastructure
behind it to provide the training and the support to the
personnel on the field that are going to use that system. If it
is a computer-based system, certainly there has to be the
infrastructure there to keep pace over the years as the
computer system gets updated or the technology gets updated. So
it is not just buying a testing tool once, there has to be the
commitment from the agency to continue using that into the
future and provide the training and resources necessary to make
sure the personnel are using it properly into the future, too.
Many times an agency will get a new tool or testing technique.
They will use it for a little bit, and then that person may
move on, that is, the one person in the agency that knows how
to use that; and that knowledge will be lost. So that maybe
comes into play a little bit when agencies are making a
decision on what technology to adopt and what equipment to
purchase.
Mr. Wu. Mr. Judycki? Mr. Tang?
Mr. Judycki. Let me just pick up on a couple of points, Mr.
Chairman. First of all, the Federal Highway Bridge Research and
Technology Program is about a $22 million program that is
available, and part of that, as Dr. Womack mentioned, it is all
designated, in fact over-designated, to the point that we were
concerned about the flexibility, or the lack of flexibility, in
putting a program together. About $900,000 is available to us
and is being used effectively in our non-destructive evaluation
laboratory and for non-destructive work on new inspection
technologies and techniques. And we can talk about that some
more. But on the barriers to innovation, which are critically
important, certainly just sheer inertia, is to new
technologies. And adopting new technology is very important, as
was mentioned. There is also a resource issue, and certainly
new technology is very often more costly without clear evidence
of long-term benefits; and that is obviously a barrier, as well
as the natural unwillingness to accept risk.
So I think that some of the solutions certainly relate to
more effective communication as we look to deployment as well
as possibly providing incentives, and providing incentives to
advancing new techniques, innovations, into the marketplace is
something that we think holds a great deal of potential.
Mr. Tang. Thank you, Mr. Chairman. I think Federal Highway
has adopted many of the innovative, non-destructive
evaluations. Over the past 20 years, we have supported a lot of
research, and many of the products are out there on the market
as a result of our research. And if you look at some of the
non-destructive evaluation, we have different phases of these
applications. For example, when you go to visual inspection and
you determine that you need a little bit more in-depth look
into a specific detail, then we will bring in the non-
destructive evaluation methods such as the ultrasonic testing
or the acoustic emission. These are more advanced than the non-
destructive evaluation that we have used, and we have offered
in our training program to include techniques so that we can
train inspectors to use them.
Mr. Wu. I am going to stretch my time just for a follow-up
with Dr. Womack. Dr. Womack, you suggested that perhaps
requiring licensed professional engineers would be a step
forward in bridge inspection. Would that help also the inertia
problem in adoption of new technologies?
Dr. Womack. I believe it would help, but one of the reasons
that you don't go beyond visual inspection is a human resource
issue. How many trained engineers do you have that can go out
and perform these inspections? And so it becomes a resource
issue in terms of trained engineers, and the number of trained
civil engineers is becoming less and less. So that is an issue.
It would help, but it is part of the problem. I think kind of
following up on the rest of the discussion, there is a
convenience issue here as well. It is very convenient and
efficient to go out and do visual inspections. They are quick,
you get some data, you can put that into the database. Non-
destructive evaluation takes more time. Usually you have to set
up equipment. Oftentimes you have to have road closures. So the
states are a little bit wont to do that because of the
inconvenience of it. I think as a follow-up to visual
inspections where there are issues, certainly NDE must be used,
and I think that is part of this protocol that has to be
defined.
Mr. Wu. Thank you, Dr. Womack. And with that, Mr. Hall.
Mr. Hall. Thank you, Mr. Chairman. You know, this is just a
terrible problem of fear of people in the driving public. In
our state, we have a State engineer and we have 254 county
engineers; and we have direct access to them to ask them
questions about it. I could ask Mr. Bernhardt whether or not
the current inspection methods are sufficient. I would like for
him to state yes. I doubt seriously that he is going to, but
you know, we even have--we have all kinds of fears. We even
have the fear of asteroids coming by, and we did a study on
asteroids about 15 years ago and found out one had come within
15 minutes of the Earth in 1988 and nobody knew it was here
until it came and went by. And it is the size of one of the
states up in the northeastern part of this country.
This is the thing that can really be fearful for people.
Every time anybody drives up on one of those high arching areas
like we have near the big cities basically. I think it strikes
some fear into their heart, what can happen. So I guess when I
ask you, Dr. Bernhardt, if the current inspection methods are
sufficient and you are going to say the factors have a lot to
do with it, I guess continuous use of it, the stress of it, the
weight at the time that the tragedy occurs, the deterioration
of the past, the force of wind or rains or your typical
westward wind or your typical eastern wind that could affect a
particular bridge or movement of the underlying earth, it is so
many things that play into that. I don't know how on Earth with
the number of bridges that we have that you can answer that
with any degree of finality, but you want to take a shot at it?
Mr. Bernhardt. Yes, sure. Statistically speaking, with
600,000 bridges, I feel safe driving over a bridge; but on the
other hand, I wouldn't be surprised if I read in the paper
tomorrow that another bridge fell down. So certainly, like any
programs, there are improvements that can be made both in the
training of inspectors, the implementation of the program, and
then what we do with the data on the back end.
I think one of the larger issues is that we don't have the
mechanisms in place now from my perspective to address the
deficiencies the inspectors are currently finding. So I mean as
an example, if we doubled our inspection frequency and
inspected bridges twice as often and produced twice as many
inspection reports and twice as many recommendations, the
ones----
Mr. Hall. And take twice as much tax money.
Mr. Bernhardt. Yeah, the recommendations we make now often
aren't addressed because the funding is not available. So
certainly, on the repair side, there needs to be some changes
there to get that caught up with the needs that the inspectors
are currently finding now. That being said, I think there are
certainly improvements that can be made in the bridge
inspection process to make it more uniform throughout the
United States, improve the certification of bridge inspectors,
both PE's and non-PE's that help in the inspection process. A
good example is, you know, in the current NBIS regulations, the
program manager position and the team leader position are the
two positions that are required to have the 80-hour
comprehensive bridge inspection training. The rest of the
inspection team is not required to have that training. Certain
states have more stringent requirements and require all members
of the inspection team to have the inspection training, but
according to the federal guidelines, you could go be an
inspector on a bridge under the guidance of a team leader who
has had the class, but it could be your first day on the job,
and you could be inspecting a bridge with probably little or no
knowledge about the performance of structures. Errors like that
can be addressed in the National Bridge Inspection Standard to
improve the quality of the inspections.
Mr. Hall. I guess asteroids are not as normal as Katrinas,
but we don't even know when they are coming. How about Dr.
Womack if I have a little time left. In your testimony you said
new inspection protocol ought to be developed; and I guess that
is what Mr. Bernhardt is talking about. Do you want to enlarge
on that any?
Dr. Womack. Currently there is a standard for the frequency
of visual inspections, but beyond that, there is really no
defined process. As Mr. Bernhardt said, you know, you can
develop a lot of data, but what does it mean and what do you do
with it? So I think we need to define a protocol where if the
visual inspection shows up issues, that there ought to be some
sort of follow-up to that rather than just more frequent visual
inspections. Maybe there should be some defined non-destructive
evaluation that needs to be performed or something else to be
done that is a little more objective than just more frequent
visual inspections.
Mr. Hall. Was that standard followed leading up to the I-35
tragedy collapse in Minneapolis?
Dr. Womack. From what I know of that situation, they were
inspecting the bridge more frequently than required. They had
some options to do some things and they just chose to continue
the more frequent visual inspection. Now, that is not to say
that if they had done something different such as putting
instrumentation on the bridge that it wouldn't have collapsed
or that we wouldn't have known about it anyway; but perhaps
with instrumentation, there might have been some precursor
information to some issues on the bridge. And so that is what
is not defined. When you do find bad things with a bridge, what
do you do next; and that is not at all a well-defined process.
Mr. Hall. I may have to do it by mail later, but I would
like to kind of know what new processes are in place and
whether or not people are following them and whether or not
they are making records of the fact that they follow them and
that we can rely on the fact that they are following them and
they are effective.
Mr. Chairman, you will leave open the opportunity for us to
write and seek answers from them if we don't get to follow-up
questions, will you not?
Mr. Wu. Yes, I will do that.
Mr. Hall. I yield back the time I don't have.
Mr. Wu. Questions will be submitted in writing, and answers
will be returned in writing. Mr. Lipinski.
Mr. Lipinski. Thank you, Mr. Chairman. I want to follow-up.
The end of the answer to the last question there, when you find
something wrong, what do you do next? What problems are we
facing right now? Is it a real need to have that type of
protocol? It certainly makes sense that it would make sense. Is
our bigger problem just a lack of taking action because of a
lack of funding to be able to do anything when we do find that
there is a problem? So is it right now largely a money problem,
or is it both a combination of a money problem and where we
just do not have the protocol in place as to okay, we find a
problem, what do we do next to try to avoid a catastrophe? So
who wants to start with that question? Dr. Womack.
Dr. Womack. I am probably not the best person to answer
that question. I would guess it is somebody from the state who
has a better feel on the available dollars would be better put.
But I think it is a lack of knowing what to do next, but I
think it is maybe an issue in terms of determining how the
available monies are spent. And coming from that point of view,
I think that you need to take more of a risk assessment
approach in terms of utilizing the funds. Where is the highest
risk, and inspections non-destructive evaluation can help you
determine what the risk is. And then you need to side on a more
risk-assessment analysis, where to spend the limited amount of
funds.
Mr. Lipinski. I will go to Mr. James since you are not the
DOT.
Mr. James. Yes, sir. If you will think of a bridge very
much like a person, a bridge is born after many months and
sometimes years of development, thought and development. They
are born, they have a life expectancy when they are first put
under traffic, 50, 75, sometimes even 100 years. As the bridge
ages due to just the natural deterioration, as we each do our
own bodies: We go to a doctor; we have a physical. We look at
things. That is an analogy to the bridge inspector out there.
He looks, he finds something. If it is something that can be
arrested to stop deterioration or to even keep it from becoming
a chronic condition, that is what we look to do to basically
preserve what we have so that we can get the fullest life
expectancy of what we have out there. Many times funding,
though, drives those decisions. I think you have heard the term
worst first? Many times that is what we have to do because we
have no choice. That is not what we would like to do because
many times that is not the best of our resources that we have.
So each state is different. We have to look at it from our
own perspective. We try to use low-cost construction,
maintenance-friendly details when we design and build our
bridges. Again, it is one thing if you are looking at an
aircraft fuselage in a hanger using non-destructive testing and
something else if you are out there 100 foot in the air on the
end of a bucket with a rope sling around you trying to
manhandle some non-destructive equipment to figure out whether
you have got a problem or not.
So, the inspector develops a relationship with a bridge. He
goes and looks at it many times, and what he is looking for is
change to see what the difference is from what he saw the last
time he looked at it.
Mr. Lipinski. Thank you. Mr. Judycki, did you want to add
something?
Mr. Judycki. Yes, and then I will turn it over to Mr. Tang.
I asked him to mention fracture critical members in a moment.
But I would just make the observation that there are some
process issues here, and I think that one of the things that
Federal Highways has very much as part of our culture, is to
make improvements in processes and procedures as the need comes
to light. We did this after the 2001 NDE evaluation of
inspection techniques that really resulted very directly in
quality control and quality assurance and additional training
being required as well as the operating inspection
certification. So, I think that the ability to learn from these
experiences and build it into national processes and
certification standards in the NBIS program becomes very
important.
With that though, I think that if I could turn it over to
Mr. Tang, I would.
Mr. Tang. Mr. Lipinski, I think you mentioned about the
finding. If an inspector finds something wrong with the bridge,
what do you do? In our National Bridge Inspection Standards, we
do have a term called critical finding. Then every inspector
when they attend training, the first thing they are told to do
is if they see an unsafe bridge, close it. That is the
immediate action that they have to take. After that, they would
have to bring in their more experienced people to determine if
they should keep the bridge open for traffic or should they
repair it immediately. So in terms of critical finding, if
there is such a critical finding on the bridge, they would have
to immediately repair it, fix it, or close the bridge. That is
in our regulations.
Mr. Lipinski. If the Chairman will let me just ask for a
brief follow-up. How often does it happen? How often are
bridges closed because it is a very difficult thing to do, to
close a bridge because of inconvenience in some locations? How
often is that done? Do you think--how bad does a bridge have to
be and how often is it done?
Mr. Tang. First of all, even during inspection time, when
you have inspection equipment on the bridge, there may not be
room for opening to traffic; so sometimes they do close part of
the bridge to even get the inspection gear into position to
inspect it. Now, how often, this is the question that we don't
have the answer in the sense of a broad answer for it. It is
left up to the inspectors. They are trained to determine that
when they need to close a bridge, they will close the bridge.
Mr. Lipinski. Thank you very much.
Mr. Wu. I would like to thank the gentleman. The gentleman
from Georgia, Dr. Gingrey.
Mr. Gingrey. Thank you, Mr. Chairman. Mr. James, I enjoyed
your analogy, as you know I would as a physician member. I
would say that a follow-on to Mr. Tang's remarks in regard to
Mr. Lipinski's question about if you find something, when do
you say, you know, we are going to have to inconvenience the
public. We are going to have to shut this bridge down for long-
term safety, maybe a short time shutting it down. It is kind of
like the individual patient. You can tell them that they need
to do something, but you can't make them do it. But I think
people at the state level, Mr. James, certainly have the
ability to say you are going to be inconvenienced. I was in New
York a couple of weekends ago, and I had the opportunity to
drive through the Lincoln Tunnel and then later on across the
Brooklyn Bridge, both aging structures; and after this
Minnesota tragedy, I couldn't help but think about when the
last time they had been inspected.
But my comments are getting to a question that I am going
to address to Mr. Bernhardt. But again, Mr. James, your analogy
to the human being, there is a test that is a little bit more
than an X-ray that looks for calcium in and around the heart.
And I have a good friend that had that test done, and the
doctor said, oh, you have got a tremendous amount of calcium
showing up on this test. Therefore you need to have an
angiogram. You need to have a dye study of your coronary
arteries. It was completely normal. And that test is expensive
and not without some risk. So what I am saying is, there are
certain tests that show something, but it is not significant,
though that calcium was all outside of the arteries. It wasn't
inside the arteries.
So Mr. Bernhardt, the question is do you think that visual
inspection, even though you are talking about professional
engineers and highly trained, motivated people, can get the job
done? What are the limitations of purely doing it that way, and
do we need to move quickly toward better testing? And if there
is time, Mr. Chairman, and maybe in the second round if there
is not time, I want to go back to Dr. Womack's comments and his
opening statement and also Mr. Judycki in regards to this issue
of programming or earmarking away a lot of funding in SAFETEA-
LU that took the ability out of your hands to use that money to
do research programs. You know, I don't want to get too
political here. We all have member initiatives, and I am one of
them. I got these great programs in the State of Georgia that I
want to see funded, but I think we need to talk about that, Mr.
Bernhardt.
Mr. Bernhardt. Yeah, visual inspection, in and of itself,
certainly isn't going to give you enough information to gather
the data that you need to make effective decisions about bridge
rehabilitation. It must be supplemented with testing, both non-
destructive and destructive testing; and in some cases the
structural health monitoring is what holds so much promise for
the future, too, because the structural health monitoring can
provide a continuous data stream, whereas if I go out and do
NDE, non-destructive evaluation on a bridge today, that is
showing me what the conditions are like today. If I have
monitoring equipment installed on that bridge that is giving me
continual feedback, it can even be set up to have alarms where
it is monitoring the stresses in the members. I am getting more
of a continuous feed of data. So certainly that is an advantage
for that type of testing. Visual is only going to provide you
with so much, and it is going to be very qualitative data. It
is going to be subjective. I am going to rate something a four,
somebody else is going to rate something a six; and I pass that
information on to the decision-maker and policy-makers, and
they are like, well, what does this mean? I got two different
answers coming. And that is because visual is very subjective.
The more testing and instrumentation we can do, that helps to
make the whole process much more objective. So that is a big
benefit for that, too.
Additionally, when you have hard data being supplied to
you, you can make more effective decisions about which bridges
do I need to direct my funding towards. You may have a
condition rating on an element that says that this bridge is in
poor condition. Well, the actual stresses in the member may be
okay. So by doing some instrumentation and further analysis,
you may be able to determine that the bridge doesn't actually
need repairs, and that money can be directed somewhere else.
And you wouldn't be able to tell that through visual alone, but
only through testing and analysis and modeling would you get
the answers to those questions.
Mr. Gingrey. I see my time is expired, and I guess the
second part of that question I will save to the second round,
Mr. Chairman.
Mr. Lipinski. I thank the gentleman. The gentlelady from
Texas, Ms. Johnson.
Ms. Johnson. Thank you very much, Mr. Chairman. I guess
that my question could be directed to the representatives. In
SAFETEA-LU there were a number of bridges designated because
the states had them on their critical list. However, I don't
know--in Texas, I have over 50,000 bridges. And I-35, which had
the collapse in Minnesota, is one of those bridges designated.
And I did earmark the money, and I will do it again; and I am
never going to stop earmarking, because if we don't, my areas
don't get anything. And so I just want to know that when you
decide through examination what bridges are in critical
condition, how do you handle it? Do you go to your Congress
people or feud about it or what happens?
Mr. James. Ms. Johnson, we work within the resources that
we have. If we find a bridge with critical needs, then many
times we will direct the resources from one part of the program
to that particular area so that we can make a rehabilitation or
replacement of that structure so that that problem goes away.
It is a matter of prioritization and taking into account many
factors in those decision as to which bridges receive the
critical treatment first. Of course, if one is about to be
closed or hopefully never reaches that state, then obviously
many more resources are directed toward it to keep things open.
They take into account the impact on the general public as well
as the safety of the public as well.
Ms. Johnson. Well, you indicated that visual decisions
after bridges are inspected usually can be considered accurate.
And what other methods do you use to inspect the bridges?
Mr. Bernhardt. I will take that one. Essentially, are you
speaking specifically to what type of testing techniques?
Ms. Johnson. Yes.
Mr. Bernhardt. There is a number of tried and true ones
which are commonly used by many state DOTs, magnetic particle,
ultrasonics, dye penetrant for steel bridges, ground-
penetrating radar, impact echo. Those are all concrete methods
that work on concrete bridges. FHWA has a Bridge Inspector's
Training Manual, and it details more than a dozen common
testing techniques; and the bridge inspection training that
team leaders and program managers take cover all these
techniques. Additionally, State DOTs have seminars where they
train their people on how to use those. So those are kind of
the tried and true methods.
And then there is a whole host of emerging technologies.
Some work out, some are just a flash in the pan. But those are
the main ones.
Ms. Johnson. Thank you. You know, the states had
rescissions even after the money was sent out the last time. So
we still don't have any work going on on those so-called
critical bridges, but hopefully it will begin soon. There is no
money in Washington, as you know, and I don't think there is
very much in states because my state just told me that they had
no money for maintenance, which is maintenance that was very
important. And so, we have a bipartisan committee out of our
delegation. We are going to be getting together to see how we
handle it. So if you don't get any federal dollars any time
soon for this, how would you handle a critical bridge?
Mr. James. Again, we work with the resources we have. If
there are needs of a bridge, we will direct state dollars for
it to keep it from being closed to take whatever actions are
necessary for it to remain safe and open to the public. Again,
we use best management practices, we use details from our
design and construction that are maintenance friendly, proven
to be very cost-effective during the construction as well as
details having longevity and are also friendly to bridge
inspection. So you do whatever is appropriate as far as the
inspection visual. It is by far, you know, the easiest and the
first place to start; and the more complex a bridge structure
becomes, you go from there using whatever technologies are
available to you. And the same thing would be with the repair,
whatever is appropriate. You take whatever actions are
necessary. Very similar to Dr. Gingrey's comments about the,
you know, a patient. Sometimes you look and you find something
and it is there but it is not a problem, so you just continue
to monitor it.
Ms. Johnson. Unpredicted weather conditions that occurred,
have you known any bridges that might have checked okay and
then after that, some kind of catastrophe, you find it is in a
different shape? I am sorry. I hope I am not giving a
confusing----
Mr. James. No, ma'am. I can't speak for every state what
each state has found. I know in our state we have not found
anything that is, you know, weather related. Obviously the two
bridges we lost from Katrina were weather related, but I don't
think anybody could have prevented some act of God like that.
As far as something that we look at one year and then come back
a year later, nothing that has led to any catastrophe or
tragedy within our state boundaries.
Mr. Bernhardt. In terms of weather related problems with
bridges, probably the greatest one is what is known as scour.
Essentially when you have a bridge, you have a big rainstorm
event, the stream fills up with water, the velocity of the
water increases, and it will scour out around the foundations
for the bridge; and there have been bridge collapses that
resulted from scour. So scour is certainly one of those
critical items that bridge inspectors pay attention to and
monitor stream beds, and if there was one primary weather
related cause of bridge failures, it would have to be scour.
Ms. Johnson. Thank you very much, Mr. Chairman.
Mr. Wu. Thank the gentlelady. The gentleman from Michigan,
Dr. Ehlers.
Mr. Ehlers. Thank you very much. My mother always told me
that scouring was good. It was a typical Dutch housewife.
When I went off to college, I started out in engineering,
and I went astray and became a nuclear physicist; and I have
always maintained a great interest in engineering and I have a
huge amount of respect for it. I was with Buckminster Fuller
once who is one of the more imaginative engineers in the
history of the profession. He commented that the first time
engineering ever really had to develop as an engineering
science was in the design of boats because you had to design
the boat very carefully using minimum materials, minimum weight
to carry maximum load, whereas before in building buildings,
for example, you just kept piling the bricks on until you were
safe or even the Roman aqueducts which have survived for 2,000
years. They used a lot more bricks, a lot more material than
they really needed to transport that small amount of water.
There wasn't a lot of engineering then.
And you know, Buckminster is right in a number of ways. We
have really advanced. We have learned to build buildings using
the minimum amount of material, minimum amount of money, how to
accomplish the goal. I think airplanes are the epitome of
success and design in trying to use minimum weight, minimum
dollars to accomplish the task.
Bridges are another good example of that, and I am just
awed by what engineers have done in bridge design construction;
but I am not sure that we have kept up as a society in our
examination and inspection of those. And my question is first
of all, is it a lack of knowledge, and lack of technology?
Aren't we putting enough into research for non-destructive
testing techniques and so forth. Or is it another case where we
are simply as a society willing to pay for the initial
structure, whatever it may be; but we are not willing to pay
adequately for the maintenance. Can you give me any comments
indicating where we have gone wrong? Is it a lack of resources
or is it a lack of research in non-destructive testing
techniques? Any comments from anyone?
Dr. Womack. I guess I can go first. I don't think it is due
to a lack of research. We have technologies, many testing
methods that have been mentioned at this table. So we have the
ability to do it. I think you are more right in terms of we are
willing to pay the first cost, although that first cost that we
are willing to pay is the lowest we can get, which isn't always
the best. But we are willing to make that first cost. Then we
are trying to catch up with other new bridges and other
repairs, so we tend not to go back and spend the money that
should be spent in terms of monitoring the infrastructure that
we have. And so I think we need to continue to do research to
develop new technologies, but it is not a shortage of
technologies that is creating the problem.
Mr. Ehlers. Okay. So, Mr. Bernhardt. You advocated
continuous inspection. Is there much of an additional price tag
to that compared to the periodic investigations?
Mr. Bernhardt. Certainly. It is much more expensive to
instrument a bridge up that initial time. Once the bridge is
instrumented, then you get that continuous data stream. I will
just make clear too that I certainly don't advocate that for
every type of structure. Certainly focusing that on the more
high-risk structures, the structurally deficient bridges, the
fracture critical bridges, I mean, that is a good use of that
type of technology. Certainly for a 20-foot span that doesn't
see much traffic and it is very simple structurally, there is
really no need to go to that kind of expense. It is the more
sophisticated structures that you want to use that technology
on. And certainly as Dr. Womack indicated, technology exists
now to do those things, so it is not on the research end. It is
getting the projects funded to put into practice where the
shortfall is.
Mr. Ehlers. Thank you. Mr. James, you were kind enough to
single out the State of Michigan as having an excellent bridge
management system. Frankly I don't know of any bridges that
have collapsed recently in the State of Michigan, and we have
built the Big Mac which has stood firm for 50 years now this
year. I appreciate your comments. But again, this is another
related question about causes of bridge failure. You mentioned
scouring. That applies to any bridge. Michigan, as well as
Minnesota, suffer a lot of damage through the freeze-thaw
cycle, Michigan much more than Minnesota because Minnesota, for
better or for worse, freezes over in November and doesn't thaw
until March sometimes. I used to live there so I know. Whereas
Michigan has probably 15 freeze-thaw cycles they go through in
the course of a winter. Maybe that is extreme but doesn't that
cause a lot of damage to bridges? I know it does to highways,
but what about bridges? Is that a factor there, too, the
constant temperature changes?
Mr. James. Yes, sir, it is, and that is taken into account
in the design of bridges and their construction and the
materials and the properties of the concrete for instance in
the deck when they are constructed. There are many things that
can be due to prescribe a particular mix that will minimize or
at least mitigate these temperature changes that you mentioned.
We are fortunate in the south that we don't experience things
like that. We typically don't use salt, either, because we
don't have the ice and snow to deal with except, you know,
those very few times within any season. There are things that,
you know, can be done. Again, it goes back to doing what is
appropriate, trying to narrow the focus of where these
technologies are needed to the high-risk bridge candidates as
much as possible using engineering--experience counts a lot for
what you are doing. Bridges again have lives 50, 75, even 100
years in some cases. Many times that is not by design but just
by necessity that bridges have to last longer than they were
ever thought to. With that, if you look at a bridge that is 50
to 75 years old, I have been with the state DOT almost 26
years. That is nearly two careers for somebody in my position
to see, you know, the life of a bridge; and many times, it
takes a structure that is, you know, 30 to 40 years old before
something comes up, very similar again to the analogy with a
person; and you do whatever is appropriate. You know, you find
something that requires constant monitoring, you look at it
until you get it arrested or corrected. If you find something
else that you need to look at, you look at it once and then you
don't go back in there. You wouldn't expect to find it again
for five to 10 more years. However you would still do the
routine physical so to speak, the visual inspection of the
bridges.
Mr. Ehlers. And one last quick question on a slightly
different subject but same problem. Dams, and I am not talking
now about the huge dams, I am talking about the smaller dams
that we have dotting the landscape of our country that we used
for power generation years ago. Is it as important to have a
constant inspection program for the dams? Is that as much of a
problem or don't they suffer as much stress or as much failure
as the bridges?
Mr. James. While those are not under my purview as highway
engineer, in many cases we have dams adjacent to roadways, and
obviously we are concerned with them. Many states or most
states have monitoring procedures whereas dams have to be
inspected on some frequency, just similarly to bridges; and
where appropriate, they could be monitored and from that
monitoring you could determine whether or not that you have an
intrinsic or chronic problem with a structure.
Mr. Ehlers. My time has expired. I yield back. Thank you.
Mr. Wu. Thank you very much, Dr. Ehlers. We have a floor
vote coming up fairly soon, so we are going to proceed with
another round of questions. We will probably proceed pretty
quickly, and the Chairman recognizes himself.
There are bridges in this country that have lasted 50 or
100 years. There are bridges elsewhere, the Roman aqueducts,
bridges in China, that have lasted 1,000 years; and the bridges
that have lasted a long time were both conservatively, perhaps
over-engineered, they have lasted a long time. We have newer
bridges that are being built with the assistance of computer
modeling and, you know, just going if you will closer to the
limits of what design and materials can do. Do these new
designs necessitate different approaches to bridge inspection
and bridge safety?
Mr. Bernhardt. Yeah, I would certainly answer yes to that
question. A good example would be the use of post-tensioning or
pre-stressing of concrete beams in bridges. You may have post-
tensioning cables inside of a bridge to give it strength, but
you could never see through those cables. So certainly you
constructed a bridge where one of the primary structural
elements you will never be able to visually see. In that case,
you must have some type of sophisticated, non-destructive
evaluation method to examine those structural elements 25 years
from now, 50 years from now as those elements start to
deteriorate inside the bridge itself.
Dr. Womack. Let me add a couple of words to that. This is
where I think the research in non-destructive evaluation can
occur. We have developed technologies to look at the bridges we
have. Now, with these newer bridges and newer construction
methods, we don't necessarily have the technologies to assess
those as in post-tension or pre-tension bridges. So we need to
develop through research concepts that we can use to non-
destructively evaluate these newer types of bridges. So along
with the new design, we need to come up with new ways of
evaluating them through testing.
Mr. Judycki. Let me just add a couple of things and then
just ask Mr. Tang to follow up. Quite a lot of the research
investments now are in new materials for bridges and it is
critically important that as we explore the application of new
material, ultra-high-performance concrete, high-performance
steels and so forth--that we assure in advance that we build
that into codes and standards and specifications as we
implement around the country. SAFETEA-LU in fact directs quite
a lot of resources into research into new materials that will
lead to new designs as we conduct our research.
Also, I had mentioned earlier the Bridge of the Future.
Much of what we are talking about really needs to be put in the
context of where we should be looking for the future and where
research can bring us in the future. The Long-Term Bridge
Performance Program was mentioned by a couple of people here at
the table. And it is critically important that we collect
information and data over a long-term so that we can develop
predictive models on deterioration and impacts of maintenance
on bridge systems. When we are really talking about a bridge of
the future, that we will have bridges that are not only
constructed with ultra-high-performance materials but also
sensing systems that will help us a great deal in overcoming
some of the barriers that we are now facing with inspection
programs.
Mr. Tang. Mr. Chair, I believe when you mentioned about the
deterioration rate of different types of bridges, they indeed
have differences. Most of the damage comes from corrosion, and
if you look at the bridges that we built in the past, corrosion
has been the major contributor to bridge deficiency; and as a
result, Federal Highway has done a lot of research on corrosion
aspect of it. If you look at 20 years ago, 25 years ago, we
didn't have any corrosion protection on our deck. Federal
Highway went out and did the research, and using the results,
we are now requiring, or we then have required a corrosion
protection system on our deck system to make it last longer.
And also, our corrosion research in our Turner-Fairbank
Facility has also looked at epoxy-coated rebar, and now we are
looking at galvanizing those rebar and stainless steel, which
we are implementing in our projects now. And in the design
code, the AASHTO LRFD code requires a 75-year design life, and
they actually have criteria specifying that design life to be
considered in the design.
Mr. Wu. Thank you very much. My understanding is that Mr.
Hall has no further questions at this point. Dr. Gingrey?
Mr. Gingrey. Thank you, Mr. Chairman. I want to state at
the outset when I made that comment about directed initiatives
and the concern that it might handcuff the bureaucrats as we
like to say sometimes, not meaning that in a pejorative way
from making decisions, certainly my colleague from Texas, if
every Member's member initiatives were as good and honest and
forthright as hers are, we wouldn't have a problem with
earmarks I am sure. But I just, you know, brought that up
because I am concerned that maybe there are certain areas in
which member initiatives may not be appropriate if it takes
funding away from something that we need to do.
But let me get to my question. I just wonder if there is
some technique other than visual inspection. We talked about
that a lot at this hearing, and we know that we have good
visual inspectors. But is there some technique non-destructive
that can be used as a retrofit for existing bridges? The bridge
of the future, I think that is probably easier to deal with in
how we construct new bridges and sensors and things that we can
put. But is there something that we can use in existing
structures in a non-destructive way that goes far beyond visual
inspection?
Mr. Bernhardt. I will take a stab at that one. Basically I
think what you are asking is--I mean, there is no magic bullet,
first of all. There are many different types of bridges, and
what technique works on one certain type of bridge will not
work on another one. So there are many specific types of
testing that work on specific bridges. I think what holds the
greatest promise would be structural health monitoring. If you
can instrument a bridge and thus know day to day a little bit
more about what is going on inside that bridge, that reduces
your level of risk. I mean, engineers tend to be conservative
by nature, and if I have to make a decision to close a bridge
or keep it open, I am going to typically be conservative. But
if I have hard data that I can look at each day that lets me
know how that bridge is behaving, then maybe I can stretch the
life of that bridge a little bit longer because I get a better
comfort level since I am getting that data. So instrumentation
can give you that.
Mr. Gingrey. Anybody else want to comment on that?
Mr. Tang. Yes, I believe some of the sensor technology is
very good, and some of the existing bridges we have used
acoustic emission monitoring or ultrasonic type testing device
and sensor technology on that now we are hoping to research to
find ways to put them into practice. For example, it is not
like one-size-fits-all as Mr. Judycki mentioned earlier. We
have to look at the specific problem and the nature of the
needs of the bridge. I think there are technologies out there
that will be appropriate, and we just need to further develop
them because right now a lot of that information is available,
but it is not proven. And as Mr. James mentioned earlier, we
are looking at proven technology. And so it would take time to
develop some of these into usable results so that you don't
just have a lot of data coming in and not knowing what to do
with those data.
Mr. Gingrey. Thank you, Mr. Chairman. I yield back.
Mr. Wu. Thank you. And as we bring this hearing to a close,
I want to thank our witnesses for coming, in some instances,
very long distances and for testifying before the Committee
today. The record will remain open for additional statements
from Members and for answers to any follow-up questions the
Committee may ask of witnesses. The witnesses are now excused,
and the hearing is adjourned.
[Whereupon, at 11:38 a.m., the Committee was adjourned.]
Appendix 1:
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Answers to Post-Hearing Questions
Responses by Dennis C. Judycki, Associate Administrator, Research,
Development, and Technology, Federal Highway Administration,
U.S. Department of Transportation
Questions submitted by Chairman Bart Gordon
Q1. One of the major challenges facing the Nation's bridges is
significant growth in traffic loads, including a greatly increased
number of long haul trucks, which stress bridges far beyond the loads
engineers originally anticipated. In his testimony, Mr. James said that
the volume of freight is actually expected to double in the next 20
years. How do current research projects, such as the Bridge of the
Future project at FHWA, take into account the continuing growth in the
number of cars and trucks using bridges? Do we need additional research
or data to accurately model the types of loads bridges will be handling
in 50 or 100 years?
A1. The issue of traffic growth impacts existing structures more so
than newly designed structures. Today's bridge codes and standards
account for the current legal weight of trucks, regardless of the
number of vehicles. Assuming that truck weights do not increase
significantly, structures designed today should be able to accommodate
the volume of, and growth in, the number of vehicles crossing a typical
highway bridge in the United States.
However, traffic growth will impact existing structures, especially
those that were constructed in the 1940s through 1970s, more directly.
Legal truck loads have increased over this time, resulting in a number
of ``load posted'' bridges throughout the United States. In addition,
our knowledge of how certain types of steel and concrete members and
details perform under repetitive loading has increased since these
structures were designed and constructed. Bridge owners are fully aware
of the potential impacts and solutions required to provide adequate
levels of safety in these existing structures under the current maximum
legal vehicle weights. This is typically done by limiting the maximum
loading, inspecting important structural details with more advanced
tools and on a more frequent basis, or by retrofitting these structural
details.
Two FHWA programs, the Bridge of the Future and the Long-Term
Bridge Performance Program, are directly focused on providing better
knowledge and tools for ensuring long, reliable service of the Nation's
highway structures. The Bridge of the Future project is focused on
design, materials, and construction practices that will make possible
significantly longer performance for newly constructed (or
reconstructed) bridges, so that they require less maintenance in the
future, while also being more readily adaptable to meet changes in
demand (for example, simple methods to add additional lanes when
traffic volumes increase significantly). The Long-Term Bridge
Performance Program is focused on developing quantitative data on the
things that impact existing bridge performance, such as load,
environment, and typical maintenance practices. This program will
result in better knowledge and tools to more effectively and
economically manage the hundreds of thousands of highway structures in
the future.
Q2. Many bridge inspection technologies are not adopted by State DOTs
because inspectors simply find them too technical and difficult to use.
How can we balance the need for detailed, accurate information and user
friendly design?
A2. The problems that bridge inspectors experience are similar to
problems experienced in the inspection of other types of
infrastructure, including buildings, pipelines, offshore oil platforms,
and dams. There is therefore a significant amount of effort ongoing
throughout the United States and worldwide to develop new and improved
infrastructure inspection tools and approaches. As a result, the state-
of-the-art in infrastructure inspection is changing and improving on a
continuous basis and we anticipate dramatic improvements in these
inspections tools and their availability in the next five to ten years.
There are several impediments, however, to the adoption of these
new tools and technologies by bridge inspectors. As pointed out, some
of the current tools are too technical or difficult to use, especially
in the harsh environments and difficult access typically found at
bridges. This is being overcome by continuous improvement in these
technologies--by making the information provided more readily
understandable; by making the tools smaller, lighter, and more
portable; and by decreasing the cost so that bridge owners and
inspectors can better afford these new tools. However, education and
training on the use of these new tools is also required. Through the
training courses developed and delivered by our National Highway
Institute, FHWA educates inspectors on new technologies to overcome the
issues of technical complexity. FHWA is committed to working with
industry and bridge owners to address each of the potential
impediments.
Q3. Of the new technologies developed at Turner-Fairbank Highway
Research Center or in collaboration with FHWA, how many are currently
in use by bridge inspectors? Which programs, such as the Local
Technical Assistance Program or National Highway Institute courses,
have been most effective for technology transfer? What have been the
biggest barriers to adoption, and what has FHWA done to try to overcome
those barriers?
A3. Over the past 15 to 20 years, a number of bridge inspection and
monitoring technologies have been developed or supported through the
efforts of FHWA's Turner-Fairbank Highway Research Center (TFHRC).
Overall, we can identify approximately 15 specific sensors and system
types, many of which have been commercialized or are currently being
refined for use by the commercial sector.
Examples of these technologies include the following:
FHWA developed a system to measure vertical and
rotational stiffness of bridge foundations using truck loads as
a method to differentiate between shallow and deep foundations
on bridges where the foundation type is unknown. The
methodology was subsequently commercialized and is currently
available from a firm located in Arlington, MA.
FHWA developed three-dimensional imaging capabilities
using ground penetrating radar (GPR) technology, enhancing the
ability of GPR to detect deterioration in concrete bridge
decks. The technology has been adopted by commercial GPR
venders and is used for rapid evaluations of multiple bridge
decks, providing information for bridge management and asset
management decision-making.
FHWA developed a sensor to passively measure the
maximum strain experienced on a bridge to detect and quantify
overloading. The sensor has been commercialized and is
currently available from a firm in Alpharetta, GA.
In cooperation with Southwest Research Institute (San
Antonio, TX), FHWA developed and evaluated systems for testing
large bridge cables using the magnetic flux leakage principle.
The technology has since been commercialized and is being
marketed by several companies.
FHWA developed methods and engineered systems for
rapidly applying thermal imaging for the detection of defects
in concrete bridge components. This has since been
commercialized and is marketed as Infrared Thermography, and is
used on a limited basis for bridge inspection.
FHWA continues to support the development of new bridge inspection
and monitoring technologies and to assist in the improvement of
existing technologies. We also actively promote and provide assistance
in the use of these systems. Ultimately, however, a key measure of
success of any highway technology depends on its acceptance by
stakeholders on a national scale. FHWA's responsibilities for research
and technology (R&T) include not only managing and conducting research,
but also sharing the results of completed research projects, and
supporting and facilitating technology and innovation deployment.
The FHWA Resource Center is a central location for obtaining
highway technology deployment assistance. Similarly, education and
training programs are provided through the FHWA National Highway
Institute. These, along with the capabilities provided by the Local
Technical Assistance Program (LTAP), Highways for LIFE, and other
similar DOT-sponsored programs and activities provide the basis for an
effective technology transfer program.
There are, however, a number of barriers to technology deployment
that may explain the relatively slow adoption of highway technologies
that appear cost effective. Lack of information about new technologies
is one barrier that may be overcome with information and outreach
programs. Long-standing familiarity with existing technologies, gained
through education or experience, also may hamper the adoption of newer
technologies, but the education and training programs provided by FHWA
and others often help to transcend these types of barriers.
It also may be difficult for stakeholders to envision the long-
range benefits of a new technology relative to initial investment
costs, especially if the payback (break-even) period is long. Even if
stakeholders are aware of eventual cost savings from a more efficient
or effective highway technology, they may have confidence in
traditional methods. Demonstration projects that provide hands-on
experience can help tip the scale so that stakeholders are willing to
apply innovative technologies to long-standing safety and asset
measurement and protection problems.
Despite these efforts, technology deployment often is slowed by
residual uncertainties about performance, reliability, installation,
and maintenance costs; availability of the next generation of the
technology; and the need for the necessary technical and physical
infrastructure to support the technology in question.
Q4. In his testimony, Dr. Womack argues that the laboratories at
Turner-Fairbank Highway Research Center (TFHRC) are underutilized. At
what percentage of capacity are the labs at TFHRC being used? What
types of projects are being delayed or foregone because of budgetary
and other limitations?
A4. Research and development work conducted by the Federal Highway
Administration is managed and directed by FHWA technical experts, and
is primarily awarded through competitive contracts. Much of the work is
done at the TFHRC--the only national highway research center in the
United States--or is managed by FHWA research staff. In addition to
competitive contracts, FHWA also works in close collaboration with
University Transportation Research Centers (UTCs), and with other
organizations in limited situations via cooperative agreements and
research grants.
The FHWA bridge and structures R&T program is authorized in
SAFETEA-LU through the Surface Transportation Research, Development,
and Deployment Program (STRDD). However, statutorily designated
projects and programs in STRDD actually exceed the authorized contract
authority of $196.4 million for fiscal years (FYs) 2006-2009. The over-
earmarking of all authorized STRDD funding necessitates across-the-
board funding reductions and results in FHWA being unable to provide
for any discretionary or flexible spending beyond those earmarks. This
lack of flexible funds severely limits FHWA's ability to investigate
and respond to current or emerging research needs that do not have
specific statutory funding.
In addition, this lack of R&T funding flexibility within SAFETEA-LU
does not allow FHWA to carry out some critical programs and
initiatives. For example, as a result of the I-35W bridge collapse in
Minnesota, the country recognizes the need for a higher level of
investment to improve bridge inspection and evaluation technology. The
lack of flexibility and the full designation of all SAFETEA-LU R&T
funds, however, prevent FHWA from adjusting priorities as a result of
tragedies like I-35W.
Some TFHRC structures R&T program laboratories, including the main
structures testing facility, are essentially at capacity as a result of
programs authorized in SAFETEA-LU and included in the annual FHWA
appropriations. Other laboratories, such as the aerodynamics,
hydraulics, and bridge management information systems laboratories,
have only marginal funding via SAFETEA-LU, but have effectively
leveraged other sources of funding so they can continue to conduct
important research and technology studies. Leveraging funding from
multiple States via the Transportation Pooled Fund (TPF) program is an
example. However, the lack of flexibility noted above does impact
FHWA's ability to address national research needs and priorities to
which these laboratories could contribute.
Questions submitted by Representative Ralph M. Hall
Q1. In 2004 the Federal Bridge Program provided $6.6 billion in aid in
addition to $3.9 billion in State and local funding yielding
approximately $10.5 billion a year in bridge rehabilitation and
construction investments. Compared to this amount, how much money is
invested in bridge safety research and development? How does the
funding for bridge related research compare to the total research
investment in the transportation sector? Has the funding received by
Turner-Fairbank been sufficient to keep your experts working at full
capacity?
A1. The Surface Transportation Research, Development, and Deployment
Program (STRDD) has contract authority of $196.4 million but, in FY
2007, was funded at only $180.8 million due to the limitation on
obligations. Of the $180.8 million, about $22.4 million (12.4 percent)
was designated for bridge and structures research and technology.
For STRDD, statutory earmarks and statutorily designated programs
authorized in SAFETEA-LU total $228.8 million in FY 2007, which exceeds
the authorized funding level. With the cuts required to all STRDD
programs in order to stay within contract authority and those required
to stay within the obligation ceiling, only about 79 percent of the
authorized funds were made available.
However, the designation and earmarking of all authorized STRDD
funding for FYs 2006-2009 created more of an issue than a funding cut.
Over-designation and over-earmarking also resulted in the inability to
provide for any discretionary spending. Thus, there is no funding for a
number of programs that are authorized by Congress, and FHWA believes
are critical to delivering a sound R&T program, but which do not have
specific statutory funding. Annually, there are about $30 million in
research and technology activities and programs that were funded in the
Transportation Equity Act for the 21st Century (TEA-21), the
authorizing legislation prior to SAFETEA-LU, that are not able to be
funded in SAFETEA-LU because all STRDD funds are designated.
In addition to bridge and structures research being conducted by
FHWA, a number of other organizations sponsor bridge research, and a
much larger group of agencies conducts bridge R&T. Included among these
are State DOTs, industry, other federal agencies, and academia. FHWA
actively coordinates the National research program with our partners
and stakeholders for agenda-setting, and in the conduct of research and
delivery of new innovations. FHWA staff participate in numerous
national and international organizations and serve on committees
focused on bridge research, development, and technology transfer. FHWA
organizes formal technical advisory groups and technical working
groups, comprised of federal, State, and local transportation
officials; bridge engineering consultants and industry groups; and
academia. Further, numerous organizations in other countries also
conduct bridge research, and other transportation modes, including the
railroad industry, conduct a limited amount of bridge research.
FHWA technical staff at the Turner-Fairbank Highway Research Center
fulfill several important roles. In addition to the conduct of applied
and advanced research, they support the deployment and transfer of new
technologies, and also provide technical assistance to states, the
National Transportation Safety Board, and others. The range of needs,
whether it be important research studies or technical assistance
requests, far exceed the time and resources available to address these
needs. FHWA staff therefore work on a continuous basis essentially at
capacity.
Q2. How many privately owned bridges are part of the public roadway
system? Since these bridges are not required to be inspected as part of
the National Bridge Inventory, do we have any data reflecting the
structural health and safety of privately held bridges?
A2. The December 2006 National Bridge Inventory (NBI) identifies
roughly 1,865 privately owned highway bridges. However, the actual
total number of privately owned highway bridges is unknown because the
states are not required to report them to the FHWA.
Condition information is available for those privately owned
highway bridges that are currently identified in the NBI.
Q3. In Mr. Bernhardt's testimony, he aptly notes that, simply
collecting more data and providing more frequent inspections will not
improve overall bridge safety: and that eventually bridges must be
rehabilitated or replaced. The age distribution for all U.S. bridges is
remarkably flat, however. Twenty-five percent are under 20 years old.
Over half the bridges in the U.S. are under 40 years old, and over
eighty percent are under 55 years old. How much do we know now about
the rates of deterioration for bridges and how those rates change over
time? Are we confident that current levels of investment for bridge
replacement will not keep up with rehabilitation needs?
A3. Significant research has been conducted on the deterioration rates
of bridges and the individual elements comprising bridges. The rate of
deterioration is influenced by many factors. These include the original
design of the structure, the climate where the bridge is located, the
load carried by the bridge over time, and the type of maintenance
activities performed on the bridge. The combination of this wide number
of factors complicates the prediction of the rate of deterioration for
an individual structure.
It is widely recognized by FHWA and others that the type of data
currently collected and maintained in the National Bridge Inventory
(NBI) is not adequate for developing sophisticated deterioration and
life cycle cost models for bridge components and structures. That is
why the Administration requested, and Congress authorized, the Long-
Term Bridge Performance Program (LTBPP) in the surface transportation
reauthorization legislation that ultimately became SAFETEA-LU. The
LTBPP is intended to collect much more detailed information and
quantified data on specific bridge elements for a small but
representative population of bridges. Much of this data will be
obtained through advanced testing and analysis. This detailed data can
then be used to enhance and improve existing deterioration models,
improve design and inspection practices, and identify cost-beneficial
preservation activities.
While it is understood that the collection of more data will not in
itself improve overall bridge safety, the information gathered through
such activities can be useful in the selection and timing of
maintenance procedures to be conducted on the bridge. The application
of properly timed and appropriate maintenance procedures can
significantly extend the normal service life of structures, allowing
many older bridges to function adequately well beyond their original
estimated design life.
The 2006 Status of the Nation's Highways, Bridges and Transit:
Conditions & Performance report to Congress had projected that the
combined level of bridge rehabilitation and replacement investment by
all levels of government in 2004 of $10.5 billion would be adequate to
reduce but not eliminate the current backlog of economically
justifiable bridge investments, if this spending level were sustained
in constant dollar terms over 20 years. The Maximum Economic Investment
scenario presented in the report projected that an average annual
investment of $12.4 billion (in 2004 dollars) by all levels of
government would be needed to eliminate the existing bridge investment
backlog and correct other deficiencies that are expected to develop
over the next 20 years.
Q4. Mr. Bernhardt testimony notes that a FHWA study in 2001 determined
that less than eight percent of inspectors could successfully locate
certain defects in test bridges. How confident are you in the current
inspection regime's ability to consistently identify potential safety
hazards? How confident are you that they identify needed repairs before
they become major reconstruction? How does FHWA ensure that its
training courses are up to date and effective in transferring knowledge
to the trainees?
A4. The 2001 FHWA report identified several concerns with the type and
quality of inspections at that time. However, it must be recognized
that this was only a very limited sample and did not completely
represent actual bridge inspection practices. The research methodology
that was used had several important limitations, including the
following:
The inspectors involved in the project were not
necessarily representative or had the level of training
required of those who conduct in-depth or fracture critical
member inspections, yet they were tasked to do so as part of
this study.
The inspectors involved in the study were not
provided with any history on the sample bridges and were not
able to take advantage of previous engineering analysis or
information. Such information is typically reviewed by the
inspector prior to conducting the next inspection on that same
structure.
As a result of the study and its recommendations, a number of
improvements were made to the National Bridge Inspection Standards.
Specifically, the regulations were revised to incorporate a requirement
to establish quality control/quality assurance procedures, along with
additional training and refresher training requirements. Inspector
training courses and certification requirements were also upgraded,
providing for a higher level of inspector competency. And, a number of
clarifications were provided to the definitions and descriptors that
inspectors use in reporting the results of the inspections.
The results of this study were widely publicized by FHWA, thereby
creating a broad awareness of the issues and greater attention to the
need for improved quality. This report certainly provided a wakeup call
regarding some aspects of the national bridge inspection program, and
spurred significant improvements in the program. However, it is
important to note that for the current investigation on the I-35W
bridge in Minneapolis, there are no indications that the collapse
occurred as a result of deficiencies in the State's inspection program.
Q5. Many of the witnesses mentioned the Long-Term Bridge Performance
Program in their testimony as particularly critical to bridge
construction, inspection, and rehabilitation research programs. As I
understand it, the program is to provide longitudinal data on the wear
and tear on a variety of common bridge structures in the U.S. How does
this data differ from what's been collected as part of the National
Bridge Inventory for the past 40 years? Why don't we have records of
the actual performance data of all bridges in the NBI and why can't
those records be used for statistical studies of the effects of
deterioration and increased use?
A5. The National Bridge Inventory (NBI) contains information at the
bridge component level. For example, no matter how large a bridge, the
overall condition of an entire superstructure is represented by a
single number on a scale of 0 to 9. While the overall ratings contained
in the NBI can be used to some extent to judge bridge performance, they
are limited in their level of detail and sophistication.
It is recognized that the NBI component ratings are based primarily
on visual observations. Through the Long-Term Bridge Performance
Program (LTBPP), the intent is to collect much more detailed
information and quantified data on specific bridge elements for a small
but representative population of bridges. Much of this data will be
obtained through advanced testing and analysis. This detailed data can
then be used to enhance and improve existing deterioration models,
improve design and inspection practices, and identify cost-beneficial
preservation activities.
Answers to Post-Hearing Questions
Responses by Harry Lee James, Deputy Executive Director and Chief
Engineer, Mississippi Department of Transportation; Member,
Standing Committee on Highways, American Association of State
Highway and Transportation Officials
Questions submitted by Chairman Bart Gordon
Q1. In his testimony, Dr. Womack argued that the bridge deficiencies
which garner the most public attention are usually fixed most quickly,
which typically means potholes are given greater priority than
structural problems that are not part of the deck or roadway. What can
the Federal Government, State governments, academia, and the private
sector do to better communicate about bridge dangers to the public?
A1. While no one should intentionally hide any bridge deficiencies from
the traveling public, deficiencies are generally of a technical nature
such that the general public may not understand the problem. Bridges
carry loads across them and the practice of load posting a bridge with
a deficiency is the best way to communicate with the public about this
subject. A public awareness campaign to inform the public what load
posting a bridge means would be most beneficial. When appropriate
precautions are taken on a bridge that has load restrictions the bridge
is not dangerous. We as a SHA do not operate unsafe bridges--we close
them before they becomes dangerous.
Q2. In your testimony, you mention that 40 states employ an element-
level inspection protocol that is beyond the federal requirements. How
does this additional level of detail help you prioritize repairs and
rehabilitation for your state's bridges? Should this type of inspection
be required for all National Highway System bridges?
A2. The additional level of detail provided by the element-level
inspection allows us to further prioritize repairs that are needed and
determine the urgency of making those repairs. This level of inspection
should be used where appropriate. It does not provide any additional or
useful information for certain type structures.
Q3. Has the Mississippi DOT adopted any new technologies for bridge
inspection? What kinds of technologies were most successful, and why?
What sort of training did your inspectors need to effectively use the
new technology? For those technologies you decided NOT to adopt, what
was your reasoning behind that decision?
A3. A few years ago MDOT purchased and received training for an
ultrasound unit that can detect material flaws in metal structures in
certain instances. While this is not new technology it was a new tool
for us to have on hand. The training was provided by the vendor and by
a consultant whom we had contracted with in the past to perform this
type of work for us. It was helpful to have the capability in-house to
use an advanced technology of this type. However, it also takes almost
constant use of the device to remain proficient with this technology.
Consequently, we still rely primarily on consultants to perform
inspections using this technology.
Questions submitted by Representative Ralph M. Hall
Q1. In 2004 the Federal Bridge Program provided $6.6 billion in aid in
addition to $3.9 billion in State and local funding yielding
approximately $10.5 billion a year in bridge rehabilitation and
construction investments. Compared to this amount, how much money is
invested in bridge safety research and development? How does the
funding for bridge related research compare to the total research
investment in the transportation sector?
A1. From my experience 6-8 percent of total research dollars are spent
on bridge related research. This number is consistent with the
expenditures for research that is conducted at the State level in MS as
well.
Q2. In your testimony you suggest that the State of Michigan has
successfully developed an asset management system that is improving
bridge safety in that state. However, according to 2005 and 2006
National Bridge Inventories, Michigan had approximately sixteen percent
of its bridges listed as structurally deficient, four percent above the
national average. What metrics are not being captured by the NBI that
point towards Michigan's success in this area?
A2. One would have to know what their percentage of structurally
deficient bridges was when an asset management system was implemented
in MI and how long it has been used. To see noticeable results after
implementing an asset management system may take eight to ten years or
more as it would have to be worked into the project development process
with ongoing projects that were not prioritized under an asset
management system. It would not be prudent to stop work on a project
that has a large investment in it already and that may be on the verge
of correcting a deficiency or situation. Stopping work on a project
just because it has not gone through an asset management system just
doesn't make sense.
Answers to Post-Hearing Questions
Responses by Kevin C. Womack, Director, Utah Transportation Center;
Professor of Civil and Environmental Engineering, Utah State
University
Questions submitted by Chairman Bart Gordon
Q1. In your testimony, you argue that the laboratories at Turner-
Fairbank Highway Research Center (TFHRC) are underutilized. How does
this affect bridge safety? If additional funds were available, what
types of projects should be prioritized?
A1. The underutilization of laboratories at the Turner-Fairbank Highway
Research Center (TFHRC) has a significant impact on bridge safety.
These laboratories are state-of-the-art, and capable of being utilized
to research new materials, designs, instrumentation, etc. Allowing
these labs to sit idle delays the opportunities that the country has of
implementing new technologies that could close the infrastructure
investment gap. As for the issue of safety, concerns for the structural
safety of bridges that should be researched may not be, due to the lack
of funding to run the TFHRC laboratories. These could be issues arising
from the I-35W bridge collapse to the falling of panels in the Ted
Williams Tunnel in Boston.
If additional funds were made available, the types of projects that
should be executed at TFHRC are of two types: First, the type that
might be too large to do elsewhere. The main structures lab at TFHRC is
quite large and can handle very large structural elements that few
other places can deal with. Second, special types of projects; those
that might relate to unique types of bridges. The I-35W is an example
of this. It is of a fairly unique design, which raises unique types of
issues. Other bridges of this ``unique'' type could range from the
Brooklyn Bridge to the Key Bridge in Baltimore to the Sunshine Skyway
Bridge in Florida.
The Long-Term Bridge Performance (LTBP) Program will handle the
most common types of bridges that are of similar designs, structural
make-up and construction. The majority of Interstate bridges fall into
this category. They are bridges with simple steel or pre-cast concrete
girders with cast-in-place decks. This type of bridge probably occupies
about 80 percent of the NHS bridge inventory. These bridges can be well
studied under the LTBP Program, and would not be good candidates for
work in the TFHRC laboratories.
Q2. In your testimony, you argue that a new inspection protocol needs
to be developed for bridges. How would an updated inspection protocol
differ from the current inspection protocol? What types of technology
would be necessary to carry out the updated inspections? Are these
technologies currently available to inspectors, and if not, what are
the barriers to their adoption?
A2. A new well defined inspection protocol would differ from the
existing in that a well defined existing protocol does not really
exist, as far as I am aware. The I-35W bridge is a good example of
that. It was inspected, determined to be structurally deficient, but
then there was a quandary about what to do next? More frequent
inspections, repair, instrumentation, etc., what to do? In the end, the
decision to inspect annually, rather than biannually, was made. Did
that work, in hindsight and all fairness to the Minnesota DOT, no; but
would other DOT's done differently? Probably not. The issue becomes one
of cost. To instrument such a bridge in a way that could provide real
time data on its behavior could cost $500,000. To perform one time
types of tests, to check for cracks, etc., could cost upwards of
$100,000. To repair, possibly millions of dollars along with shutting
bridge down and the inconvenience that would cause. To perform more
frequent visual inspections, a few thousand dollars. But in the end,
the cost could near $1 billion in terms of reconstruction and costs to
individuals (not to mention the indeterminable cost of the loss of
life). So are we being penny wise and pound foolish? Perhaps. This is
not to say that if things were done differently the I-35W Bridge would
not still have collapsed, you simply cannot cover all the
possibilities, but a better chance of saving the bridge, and the lives,
might have existed had things been done otherwise.
The new protocol would indicate the next steps that should be taken
after visual inspection determines a bridge to be structural deficient.
The precise reasons for such a rating would be determined and the next
steps would be based the causes of the structural deficient rating.
Should the next steps be one time testing of bridge elements or an
overall load rating test; or constant, real time monitoring through
instrumentation; or minor repairs; or immediate closing of the bridge;
all of this needs to be determined and developed through research that
has the mandate of developing such a protocol.
As for the technologies, they do exist, but can be expensive, thus
they are not readily available to inspectors today. They can also be
technically sophisticated and need trained personnel to operate. Again,
this costs money. If a DOT wanted to instrument a bridge to provide
real time performance data it can be done, and has been done on a
segment of an Interstate bridge in Utah, but it is expensive. Such
instrumentation could consist of accelerometers, velocity transducers
(geophones), strain gauges, cameras, etc. All of which is available.
Currently, NBIS regulations have the first option to have a
Professional Engineer with the requisite experience and training to
perform bridge inspections but they do have other lesser options which
do not require bridge inspectors to be Professional Engineers. ASCE
believes that non-licensed bridge inspectors and technicians may be
used for routine inspection procedures and records, but the pre-
inspection evaluation, the actual inspection, ratings, and condition
evaluations should be performed by licensed Professional Engineers
experienced in bridge design and inspection. The NBIS regulations
should be changed to require just Professional Engineers with
appropriate experience such as the expertise to know the load paths,
critical members, fatigue prone details, and past potential areas of
distress in the particular type of structure being inspected as the
lead bridge inspector. They must have the ability to evaluate not only
the condition of individual bridge components, but how the components
fit into and affect the load paths of the entire structure. The bridge
engineer may have to make immediate decisions to close a lane, close an
entire bridge, or to take trucks off a bridge to protect the public
safety.
Questions submitted by Representative Ralph M. Hall
Q1. In Mr. Bernhardt's testimony, he aptly notes that, ``simply
collecting more data and providing more frequent inspections will not
improve overall bridge safety'' and that eventually bridges must be
rehabilitated or replaced. The age distribution for all U.S. bridges is
remarkably flat, however. Twenty-five percent are under 20 years old.
Over half the bridges in the U.S. are under 40 years old, and over
eighty percent are under 55 years old. How much do we know now about
the rates of deterioration for bridges and how those rates change over
time? Are we confident that current levels of investment for bridge
replacement will not keep up with rehabilitation needs?
A1. We do not know a lot about the rates of deterioration of bridges
and how those rates change over time. This is one objective of the
Long-Term Bridge Performance (LTBP) Program, to provide data that will
give an indication as to how deterioration occurs, under what
circumstances, and how it changes with time. I am very confident that
the current levels of investment will not keep up with the future
repair and replacement needs.
One very simple reason for that is the increase in the cost of
commodities that have occurred over the past five years. Prices for
steel, cement, aggregate, and last but not least, oil have increased
dramatically. Much of this is due to development overseas, China chief
among these countries. There is little evidence that these countries
are going to slow down their development in the near future.
You state in your question that over half the bridges in the
country are less than 40 years old, looking at this a different way,
then a number approaching half the bridges in the country are more than
40 years old. This is a second reason I am sure that we will continue
to experience an investment gap. A typical design life for a bridge is
50 years, as these bridges approach this age, they will need to be
repaired or replaced. This is an astronomical number of bridges, the
likes of which we have not had to deal with in the past, and we cannot
even keep up with the current surface transportation system investment
needs.
Q2. Many of the witnesses mentioned the Long-Term Bridge Performance
Program in their testimony as particularly critical to bridge
construction, inspection, and rehabilitation research programs. As I
understand it, the program is to provide longitudinal data on the wear
and tear on a variety of common bridge structures in the U.S. How does
this data differ from what's been collected as part of the National
Bridge Inventory for the past 40 years? Why don't we have records of
the actual performance data of all bridges in the NBI and why can't
those records be used for statistical studies of the effects of
deterioration and increased use?
A2. The National Bridge Inventory does not have any of the type of data
that would be collected from the Long-Term Bridge Performance (LTBP)
Program. The LTBP data will be collected mainly through live load
testing, instrumentation to provide constant monitoring of bridge
behaviors, and forensic testing of bridge elements that will be taken
from razed bridges. This will provide data outside the NBI, and will
help us to answer your first question about bridge deterioration.
We don't have the records of performance data for bridges over the
past 40 years because the technologies in instrumentation and data
collection that we have today has not existed over that time period,
and it is very expensive. Without a special program like the LTBP
Program, with funds dedicated to this purpose, this type of data would
still not be collected on a large scale.
Question submitted by Representative Daniel Lipinski
Q1. In your written testimony, you reference a current shortage of
civil engineers in the United States, as well as a clear need for
increased licensed professional engineers. How do you believe we can
encourage more students to enter this field of work?
A1. The shortage of civil engineers and civil engineering students
directly impacts the number of civil engineers that are currently
licensed and will be licensed in the future. Much of this problem is
the fault of the civil engineering profession. We, as a profession,
have done a poor job of marketing civil engineering as a profession.
Engineering students have to go through an undergraduate curriculum
that is harder than any other that exists on a college campus, more
difficult than even those that are used to enter MBA programs, law,
medical or dental schools. Unless young people are really set on going
into civil engineering they do not see the point in going through such
a difficult curriculum to be a civil engineer when they can be a
doctor, lawyer, dentist, aerospace or computer engineer and make much
more money.
As a profession, we need to do more to attract young people to
civil engineering. We need to let them know of the dire need for civil
engineers, particularly in transportation. We also need to make
salaries that young civil engineers will get more competitive with the
aerospace and electrical engineers. When articles such as the one in
USA Today on October 12th (Engineers Step up Recruiting Efforts) appear
and show the salary disparity in the different types of engineering
professions, with civil engineers at the bottom, it is difficult to
recruit civil engineers. The market will take care of some of this
difference, but by the time the market really does react and the
principal of supply and demand creates a rise in the salaries for civil
engineers, the shortage of civil engineers will be extreme, and I
believe harmful to the infrastructure of this country due to the lack
of properly trained engineers.
As for what the Congress might do to assist in this recruitment of
civil engineers, one thing that comes to mind is a loan forgiveness
program as is done for educators. If a person graduates in an
accredited civil engineering program and goes to work for a city,
county, state or other type of governmental agency their students loans
could be forgiven based on some sort of schedule. In the short-term,
this could alleviate some of the salary disparity. Another approach
would be to encourage the exposure of engineering (all types) to K-12
students. Right now they see the sciences, and are exposed to other
professions in their daily lives, but K-12 age kids really have little
exposure to civil engineers.
Ultimately, ASCE believes that it is critical to provide all
students, no matter what careers they ultimately pursue, with a strong
background in basic mathematics and science to enable them to
participate in our increasingly technical society. We must prepare
those students who want to pursue careers based in mathematics and
science with the necessary skills in these subjects. And finally, we
must encourage highly qualified students to pursue careers based in
mathematics and science and more specifically in civil engineering.
Over half of the economic growth today can be attributed directly
to research and development in science, engineering and technology. Our
ability to maintain this economic growth will be determined largely by
our nation's intellectual capital. The only means to develop this
resource is education.
Recent assessments by the U.S. Department of Education of the
progress of students' performance in various subject areas, including
science, math, engineering and technology education, have concluded
that the grasp of science and math by U.S. students is less than that
of their international peers. It is also notable that over half of U.S.
graduate students in science and math are foreign-born.
For these and other reasons, the implementation of the
recommendations of the NSB in their report on math and science
education is critical. The proposal to coordinate and facilitate STEM
programs through a National Council for STEM Education has merit and
should be supported by Congress. Other recommendations to focus
attention on STEM education in federal agencies also have merit.
Civil engineering professionals, however, hold the final
responsibility of growing the pool of civil engineers and civil
engineering students that can become licensed professional engineers.
This needs to be a PR effort and a financial one by the consultants and
government employers to increase the salaries of young civil engineers.
The American Society of Civil Engineers can, and has in the past, play
a major role in this effort and in working with Congress to improve the
environment for young people to enter the civil engineering profession.
Answers to Post-Hearing Questions
Responses by Mark E. Bernhardt, Director, Facility Inspection, Burgess
& Niple, Inc.
Questions submitted by Chairman Bart Gordon
Q1. You discuss your company's involvement in the inspections of steel
truss bridges following the I-35W collapse in your testimony, but point
out that ``in general, the inspections were carried out in the same
manner as those completed prior to the I-35 collapse.'' In your
opinion, what was the value of these new inspections? What sort of
guidance or technical assistance could FHWA provide to make these
inspections more valuable? Did the re-inspection alert you to any new
problems, and how did you or the relevant state DOT deal with those
problems?
A1. The primary value of the supplemental deck truss inspections
performed in the aftermath of the I-35W collapse was to help in
reassuring the American public that bridges are indeed safe. Since it
has not yet been determined what caused the I-35W bridge collapse;
i.e., latent design defect, construction overload, ongoing
deterioration of primary bridge members, etc., it would be premature to
redefine NBIS procedures at this time. It may turn out that the
collapse is not something that could have been prevented by enhanced
bridge inspection practices. Once the cause has been determined, the
FHWA, along with the bridge engineering community, will be able to
determine if modifications to inspection procedures are indeed
warranted. The re-inspections of deck truss bridges performed by
Burgess & Niple found no new significant deficiencies that required
immediate repairs. All findings were transmitted immediately to the
appropriate state transportation agency personnel.
Questions submitted by Representative Ralph M. Hall
Q1. In your testimony, you note that, ``simply collecting more data
and providing more frequent inspections will not improve overall bridge
safety'' and that eventually bridges must be rehabilitated or replaced.
The age distribution for all U.S. bridges is remarkably flat, however.
Twenty-five percent are under 20 years old. Over half the bridges in
the U.S. are under 40 years old, and over eighty percent are under 55
years old. How much do we know now about the rates of deterioration for
bridges and how those rates change over time? Are we confident that
current levels of investment for bridge replacement will not keep up
with rehabilitation needs?
A1. Many studies have been done with respect to methods by which to
accurately model bridge deterioration. In one accepted approach the
condition of a bridge or an element of a bridge is characterized in
terms of a set of possible condition states. The deterioration of that
element is represented as the successive occurrence of transitions from
one state to another. The likelihood of these transitions occurring
during a certain time period is dependent on such factors as loading
conditions, environmental effects, levels of maintenance and repair,
etc. Markov process assumptions are used to estimate transition
probabilities from one condition state to the next with a key
assumption being that transition probabilities are independent of the
element's previous states. Another common approach uses statistical
regression to develop relationships between condition measures and
parameters presumed to have a causal influence on condition. More
knowledge of the physical and chemical deterioration mechanisms and
further detailed study of bridge behavior would likely improve the
accuracy of these deterioration models. Although, the issue is not that
we do not know now when repairs should be made, it is that
transportation agencies lack the funding necessary to repair and
maintain their bridge inventories to the desired condition standard.
ASCE's Report Card for America's Infrastructure from 2005 concluded
that $9.4 billion per year over the next 20 years is needed to
eliminate bridge deficiencies and an additional $7.3 billion annually
is needed to prevent the bridge deficiency backlog from increasing
further.
Q2. In your testimony you describe a ``general consensus within the
engineering community that visual inspection practices must be
supported by rigorous training, certification, and quality assurance
programs.'' In your opinion, how does the current training regime
offered by the National Highway Institute stack up in these areas?
A2. The FHWA/NHI Bridge Inspection Training Program, namely the three-
week comprehensive training, is designed to bring individuals with at
least a high school diploma to entry level participation in bridge
inspection related work, notably field inspection activities. However,
in 23 CFR 650 Sub Part C National Bridge Inspection Standards, sections
650.309 Qualifications of Personnel, only three classifications of
bridge inspection staff, ``Program Manager,'' ``Team Leader,'' and
``Underwater Bridge Inspection Diver,'' have minimum qualification
requirements. Each of these classifications uses the comprehensive
training as a baseline for qualification but none of them are entry
level positions. The current minimum specifications in the NBIS for
training and qualifications for Program Managers and Team Leaders are
somewhat sound, however clear statements should be added that address
the following recommended improvements:
The current Team Leader classification title should
be modified to Team Leader I. The minimum qualifications in
NBIS for this classification are adequate for bridge structures
that are not deemed complex and for structures that are not
already classified as structurally deficient.
A new classification for ``Team Leader II'' should be
introduced for structures deemed complex and for structures
that are already classified as structurally deficient. Minimum
qualifications for this classification should include: A BS in
engineering from an ABET accredited institution, passing of the
Fundamentals of Engineering exam, at least two years experience
with bridge safety inspections and completion of FHWA
comprehensive training.
Engineering judgment is frequently required to assign
condition ratings to important structural components of a
bridge. Since the PE in responsible charge may not personally
inspect all items at arm's length, he or she must be able to
rely on a person with sufficient understanding of structural
systems to assist in the assignment of condition ratings to
structural components. The Team Leader I and Team Leader II
concept support this.
State agencies across the United States have the
ability to utilize personnel other than licensed Professional
Engineers to inspect bridge structures. This is being done
primarily because the National Bridge Inspection Standards
(NBIS) allows experience to substitute for a professional
engineering license. Under NBIS guidelines, a person without
any formal educational training in structural engineering can
be a Program Manager or Team Leader with ten and five years
experience, respectively. This should be changed to mandate
professional licensing in addition to accumulated relevant
experience for the Program Manager position. The proposed Team
Leader II classification addresses this issue with team
leaders.
Alternate specifications for comprehensive bridge
inspection training for licensed engineers and persons with a
secondary education that includes bridge engineering.
There should be a correlation between complexity of
structure, and level of training and experience. The Team
Leader I and Team Leader II concept support this.
Improvements can also be made to the certification
process. See below.
Many State DOTs already have some form of bridge inspector
certification process in place to support qualification requirements.
They review individual's experience and qualifications and issue a
unique CBI (Certified Bridge Inspector) Number to qualified inspectors
(Florida and Oregon are examples). States that do not have a formal
process often request certificates of NHI training and PE licensure
from consultants that they hire to perform inspection work as a way to
verify credentials.
Also, in many states, consultants need to be ``pre-certified'' for
bridge inspection work, just like any other engineering service, prior
to submitting on contracts.
Greater accountability demands a higher level of competency and
this can be achieved through a certification process that incorporates
rigorous testing. The current FHWA/NHI training program provides the
information necessary for competent performance. However the testing in
place primarily evaluates learning to satisfy IACET requirements for
continuing education eligibility. For the proposed entry level ``Bridge
Inspector'' and the proposed ``Team Leader I,'' this is adequate;
however for the proposed ``Team Leader II'' classification, it is not.
The introduction of a Federal Certification process would normalize
skill levels of personnel performing bridge inspections nationwide and
should include the following:
Definition of inspector classifications based on
skill levels (i.e., Bridge Inspector--1, Bridge Inspector --2,
Team Leader I, Team Leader II, Bridge Inspection Diver, Program
Manager).
Documentation of background education.
Documentation of completed bridge inspection
training.
Documentation of skill level proficiency test scores.
Documentation of relevant experience.
Assignment of a unique certification number/
designation that reflects the classification/skill level
achieved.
Issuance of a federal certificate that reflects the
classification/skill level achieved.
The NHI has the ability to track and maintain inspector
certification on a national basis. State agencies could build on a
federal certification process for specific needs and applications
within their state.
Q3. One method to push new promising technologies has been to widely
disseminate results from specific demonstrations. Are individual
demonstration projects sufficient to jump-start a transportation
technology, given the risk aversion and conservative nature of the
civil engineering profession?
A3. Demonstration projects provide the hard data that can demonstrate
the viability of emerging technologies and weed out those that do not
provide useful results. Many of the newer technologies have higher
initial costs than traditional visual inspection techniques, but are
likely to result in more cost-effective bridge management over the life
of a structure. Engineers are probably reluctant to adopt technologies
if they are skeptical of the long-term cost benefits. Proposed projects
such as the FHWA's Long-Term Bridge Performance Program will be
structured to gather the data necessary to answer questions related to
the actual cost benefits of emerging bridge testing and monitoring
technologies.
Q4. Mr. Bernhardt, you note in your testimony that a FHWA study in
2001 determined that less than eight percent of inspectors could
successfully locate certain defects in test bridges. How confident are
you in the current inspection regime's ability to consistently identify
potential safety hazards? How confident are you that they identify
needed repairs before they become major reconstruction?
A4. If an inspector is properly trained and certified; is focused on
the job at hand; understands the responsibility associated with bridge
inspection; has had the opportunity to gain experience while working
under the direction of more senior bridge inspectors; is comfortable
working within a particular bridge's environment; has adequate time
allotted and equipment provided to permit the inspector to get within
arm's length of all critical members; has at least a basic
understanding of structural mechanicals; and established quality
control and quality assurance procedures are followed, potential safety
hazards, structure deficiencies, and needed repairs can be successfully
identified.
Appendix 2:
----------
Additional Material for the Record
Statement of Christopher C. Higgins
Oregon State University College of Engineering
I thank the Committee for the opportunity to provide this written
testimony on research needs and actions necessary to help ensure the
safety of the Nation's existing bridge inventory. On-going research at
Oregon State University, funded through the Oregon Department of
Transportation, has focused on field and laboratory testing,
nondestructive evaluation, analysis, rating, and evaluation of existing
aging and deteriorated bridges. We are also applying high-performance
materials and techniques for repair and strengthening of existing
bridges as well as developing tools to more directly quantify risks
associated with operational conditions thereby enabling better informed
bridge management decisions. This testimony reflects these experiences
and addresses some of the current limitations in understanding aging
and deteriorated bridges and highlights some of the pressing research
needs.
Bridges are a unique type of structure that must withstand a wide
array of forces including wind, earthquakes, floods, impacts, and
traffic loads, among others. Further, they are exposed to variable
seasonal climatic conditions and millions of repeated cycles of load
with magnitude and volume that have continued to increase over time.
These combined influences can result in strength deterioration of the
bridge members and connections and without sufficient inspection,
maintenance, and intervention can result in collapse. Engineers have
little information on the combined influences of applied structural
loading with variable environmental conditions such as freeze-thaw,
chloride exposure, and extreme seasonal temperature changes. Some of
the new materials being developed for bridge strengthening rely on
bonding to the bridge surfaces that may be more susceptible to
environmental factors. Significant additional research on large-sized
bridge members under combined structural and environmental loading are
required to ensure performance of new strengthening techniques and
materials.
We must better address the large number of aging bridges that
remain in the national inventory. These aging bridges contain materials
and structural details that are very different from our modern design
and construction practice. Better quantifying the safety of these
bridges is a national need. Engineers commonly apply design and rating
tools developed for new bridges to older bridges often without
sufficient data to know if these are applicable. As an example,
engineers are now rating some bridges for strength (collapse state)
that were designed by an older method called working stress design
(service level state). We cannot now be certain how some of these older
designs will perform at the strength condition. There is a significant
research need to better quantify the actual strength of older bridges
that will remain in the national bridge inventory. An important focus
should be on in-situ testing to failure of decommissioned bridges using
realistic loading conditions. These tests need to be supported with
laboratory tests to make the best linkage with existing data. Research
programs like this are very expensive, but can provide significant
savings if engineers can have confidence in the tools used to quantify
remaining capacity of existing bridges and preclude unnecessary
replacement or restrictions.
Bridges often sustain damage and deterioration over time. The most
significant contributor to deterioration is corrosion. Current data
available to evaluate corrosion damaged bridge members is exceedingly
limited and generally based on small-sized laboratory specimens. This
lack of data leads to great uncertainty in predicting remaining
strength and ductility of corrosion damaged bridges. Current techniques
often assign crude reduction factors based on subjective visual
inspection of overall condition. These factors have no scientific
basis. Research is needed to develop techniques for evaluation of
corrosion damaged bridge members. This research must be on large-size
samples that realistically reflect actual bridge members and the
combined influences of applied fatigue loading with impressed corrosion
need to be considered. Additional investment in laboratory research
facilities is required to adequately address this need.
Advancement generally relies on more sophisticated techniques and
physical resources that may not be readily available within a
transportation agency or consultancy. These include more complicated
analytical and computational methods (nonlinear models, probabilistic
methods, etc.), as well software and hardware resources such as finite
element software and computing power. Having knowledgeable in-house
technical staff that can understand and fairly evaluate advancements
are critical for research adoption/adaptation. We need to be able to
educate the next generation of engineers that can supply this technical
competence and can better handle the probabilistic nature of the
problems we encounter, can understand and apply the more sophisticated
analytical techniques being developed, and can effectively communicate
with public stakeholders and inform public policy.
Additional research funding or reallocation of existing resources
between ``research'' and ``planning,'' as well as a greater focus on
bridge infrastructure by University Transportation Centers is needed. A
national research center focused on safety evaluation of existing
bridges that draws on expertise from across the country, as in the
framework of the National Science Foundation's Earthquake Engineering
Research Center program, would be a logical and fruitful outcome. There
is much research to be done to enhance our understanding of bridge
deterioration and our ability to evaluate the safety of existing bridge
members, connections, and systems. We need to develop new techniques
for evaluation of bridge infrastructure deterioration, develop health
monitoring and effective strengthening/rehabilitation approaches,
consider more directly safety and risk (specifically quantify risks)
for bridges and operating conditions, and indeed look at system level
performance to facilitate ideal resource allocation. With such
compelling research outcomes it is possible to transform the state-of-
the-art to protect the safety of the Nation's bridges.
Respectfully,
Christopher C. Higgins, Ph.D., P.E.
Associate Professor
Oregon State University
Statement of
Michael Todd
Associate Professor of Structural Engineering
University of California-San Diego
and
Charles Farrar
Leader, The Engineering Institute
Los Alamos National Laboratory
First we wish to sincerely thank the Committee on Science and
Technology for holding this hearing, and for the opportunity to present
this supplemental written testimony. We hope to add a perspective that
complements the very informative discussions provided during the live
testimony by representatives of FHWA, AASHTO, ASCE, and ACEC. It is
encouraging that the Committee has taken up the very important issue of
infrastructure (and specifically, bridge) condition and safety. Our
nation's infrastructure safety has direct impact upon our country's
economy and security, and we agree that there is no better time than
the present to investigate the current state of infrastructure damage
assessment technology to determine both what is being done and what
could be done for future improvements. While the engineering community
of bridge experts does not yet know what led to the recent I-35 bridge
collapse in Minneapolis, this disaster nonetheless unfortunately
brought to popular consciousness the dramatic consequences of such a
structural failure.
By way of introduction, we are mechanical (Michael Todd) and civil
(Charles Farrar) engineers who currently co-lead the Engineering
Institute (http://www.lanl.gov/projects/ei/index.shtml), a joint
research and educational collaboration between the University of
California-San Diego Jacobs School of Engineering and the Los Alamos
National Laboratory that focuses upon the fields of structural health
monitoring and damage prognosis. Prior to joining the University of
California San Diego, Prof. Todd had a seven-year career in leading DOD
research and development programs at the U.S. Naval Research
Laboratory, and Dr. Farrar has spent 25 years in numerous forms of
technology development, transition, and leadership at Los Alamos
National Laboratory. Prof. Todd and Dr. Farrar together have 23 years
experience in the structural health monitoring and damage prognosis
fields.
The process of implementing a damage detection strategy for
aerospace, civil and mechanical engineering infrastructure is referred
to as structural health monitoring (SHM). This process involves the
observation of a structure or mechanical system over time using
periodically spaced dynamics response measurements, the extraction of
damage-sensitive features from these measurements, and the statistical
analysis of these features to determine the current state of system
health. For long-term SHM, the output of this process is periodically
updated information regarding the ability of the structure to continue
to perform its intended function in light of the inevitable aging and
degradation resulting from its operational environments. Under an
extreme event, such as an earthquake or unanticipated blast loading,
SHM is used for rapid condition screening. This screening is intended
to provide, in near real time, reliable information about system
performance during such extreme events and the subsequent integrity of
the system. Damage prognosis (DP) extends the SHM process by
considering how such an assessment, when combined with a probabilistic
model of future environmental and operational loading conditions can be
used to forecast metrics of system performance useful to the owners,
such as remaining system life and maintenance scheduling. The
Engineering Institute is the only university/national laboratory
collaboration, to the best of our knowledge, in the United States that
is promoting a focused research-driven graduate education in the SHM
and DP fields, leading to next-generation engineers trained in critical
inter-disciplinary skills required to solve the complex SHM/DP problems
associated with long-term infrastructure life cycle engineering and
management.
This testimony will pose five questions for consideration by the
Committee. We believe that these are among the important questions that
both the engineering/technical community and the policy-makers should
be addressing as we jointly assess how the SHM/DP fields are being
applied or could be applied to infrastructure condition monitoring and
remediation.
(1) What is the current state-of-the-art in damage detection
strategies for infrastructure such as bridges?
In 1992, an extensive survey of bridge failures in the United
States since 1950 was presented by Shirole and Holt.\1\ These authors
point out that at that time the responses of engineers to bridge
failures was reactive as is the case with most unanticipated failures
of engineered systems. Bridge design modifications and inspection
program changes were made in response to catastrophic failures. The
collapse of the Tacoma Narrows Bridge more than a half century ago is a
classic example of this reactive approach because it led to the
inspection and design modifications of other suspension bridges. The
widespread introduction of the current federally mandated systematic
bridge inspection program was directly attributed to the catastrophic
bridge collapse at Point Pleasant, WV, in 1967.\2\ Design modifications
for seismic response of bridges have been made as a direct consequence
of damage sustained by these structures during the 1971 San Fernando
Earthquake (Gates, 1976).\3\ Damage leading to bridge collapse also
occurs as a result of collisions and scour (the process where increased
fluid velocity usually associated with a flood removes supporting soil
from the base of a bridge pier). For example, the AMTRAK railroad
bridge collapse near Mobile, Alabama, in 1993 resulted from the
collision of a barge with the bridge pier.
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\1\ Shirole, A.M. and R.C. Holt, 1991, ``Planning for a
Comprehensive Bridge Safety Assurance Program,'' Transportation
Research Record, 1290, pp. 39-50.
\2\ White, K.R., J. Minor, and K.N. Derucher, 1992, Bridge
Maintenance, Inspection and Evaluation, Marcel Dekker, New York.
\3\ Gates, J.H., 1976, ``California's Seismic Design Criteria for
Bridges,'' ASCE Journal of Structural Engineering, 102, pp. 2301-2313.
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At present, bridges are required to be rated and monitored during
biennial inspections, largely with the use of visual inspection
techniques. As needed, these visual inspections are augmented with
traditional local nondestructive evaluation (NDE) techniques. However,
because these NDE techniques inspect only a very small area of the
structure, they require some a priori knowledge of the possible damage
location before they can be used effectively. These techniques are not
employed in a continuous manner and, in general, they require that the
portion of the structure being inspected is readily accessible. There
is the possibility that damage can go undetected during the visual
inspections or that damage in load-carrying members can grow to
critical levels between inspection intervals as the recent collapse of
the I-35 Bridge in Minneapolis has made all too clear.
In an effort to move from the current qualitative visual
assessments to more continuous and more quantified structural health
monitoring procedures, the civil engineering community has studied
global vibration-based damage assessment of bridge structures since the
early 1980's. The fundamental premise of these methods is that the
measured vibration response of the bridge is a function of the mass and
stiffness properties of that structure. Damage will alter the stiffness
properties of the bridge and these changes will be detected in the
measured vibration response. To date, these methods, which make use of
off-the-shelf sensing technology, have only been shown to be effective
after significant damage had been sustained by the structure. These
damage levels are well beyond those that would be considered necessary
to safely shut the structure down before catastrophic failure. In
addition, environmental and operating condition variability as well as
the physical size of these structures has presented significant
challenges to the implementation of such bridge monitoring approaches.
Although numerous studies focused on the development of more advanced
structural health monitoring approaches have been undertaken, none have
been shown to be more effective than the current biannual visual
inspection techniques currently in use by state highway departments.
(2) What new technologies are under development that could aid in
infrastructure SHM/DP health management strategies?
SHM/DP technologies can roughly be categorized into sensing/
networking, which is the way various data are obtained from the
structure and managed through networks of sensors and possibly
actuators, and data interrogation, which are the algorithms used to
extract meaningful damage-related information from the data and then
use that information to form robust assessments about the structure's
current health state. Stated succinctly, SHM/DP has been enabled by the
revolution in microelectronics over the past few decades. These
advances are making more ubiquitous sensing on large-scale structures
economically feasible. Systems with greater sensor density include
traditional wired sensor networks and more recently, new wireless
sensor networking paradigms. Wireless sensor networks can potentially
better address the need for more continuous monitoring in the field,
where the traditional design of wired sensors connecting to a
centralized data acquisition and storage hub is not always practical.
Many bridges or other infrastructure simply do not have a convenient AC
power supply to which one can ``plug in'' their sensor network.
Decentralized sensor network architectures rooted in wireless sensing
and telemetry can address this issue by providing local sensing
``nodes'' where sensing, control, computing, and telemetry are all
integrated in relatively low-power platforms. These platforms can
communicate with each other as needed to move information through the
network using an energy efficient ``hopping'' protocol where data are
transmitted from node to node and eventually to a base station. While
many researchers have advanced (and continue to advance) such wireless
sensor nodes in the last 10 years (e.g., see the work by Lynch, et
al.\4\ ), these nodes still have some limitations in bandwidth (how
much data or information can move around the network in time), local
data storage (how much data or information can reside on the node
during local processing), and what types of specific sensors can
interface with them. These limitations are all related to the
availability of power. Currently, the majority of these sensor nodes
use batteries as the local power source. Although the nodes are
designed to be extremely power efficient, the batteries represent a
limited-life component that has to be periodically replaced. For large
bridge structures, the locations where one might need such a sensor
node can make it very costly to replace the batteries and can pose a
safety concern for the technician who has to perform this duty.
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\4\ A.T. Zimmerman and J.P. Lynch, ``Automated Damage Estimation in
Wireless Sensing Networks Using Parallelized Model Updating,'' 6th
International Workshop on Structural Health Monitoring, Stanford,
California, September 11-13, 2007.
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Consequently, researchers are also currently investigating
strategies that employ energy harvesting or an alternate ``on demand''
energy delivery system that makes use of power supplied by autonomous
vehicles such as small robotic helicopters or cars.\5\ The Engineering
Institute team recently demonstrated such a system for the first time
on an out-of-service bridge near Truth-or-Consequences, New
Mexico.\6\,\7\ Here the term ``energy harvesting'' refers to
the process of converting ambient energy sources available in the
bridge's operating environment to useful electric energy. Available
energy sources include solar and the bridge's own mechanical vibration
energy from traffic loading. Small commercially available off-the-shelf
solar cells are readily available to power these sensor nodes.
Mechanical energy typically is transformed into electric energy by
actuating a piezoelectric material that produces an electrical charge
when strained.
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\5\ G. Park, C.R. Farrar, M.D. Todd, W. Hodgkiss and T. Rosing,
``Power Harvesting for Embedded Structural Health Monitoring Sensing
Systems,'' Los Alamos National Laboratory report, LA-14314-MS (2007).
\6\ D. Mascarenas, M.D. Todd, G. Park, and C.R. Farrar, ``A Low-
Power Wireless Sensor Node for Peak Displacement and Bolted Joint
Preload Measurements,'' 6th International Workshop on Structural Health
Monitoring, Stanford, California, September 11-13, 2007.
\7\ M.D. Todd, D. Mascarenas, G. Park, C. Farrar, K. Farinholt, T.
Overly, and M. Nothnagel, ``A Different Approach to Sensor Networking
for SHM: Remote Powering and Interrogation with Unmanned Aerial
Vehicles,'' 6th International Workshop on Structural Health Monitoring,
Stanford, California, September 11-13, 2007.
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From the sensing perspective another area of emerging technology is
the use of active sensing technology. Most earlier work on structural-
health monitoring strategies for civil engineering infrastructure
relied on the ambient loading environment as an excitation source and,
hence, are referred to as passive sensing systems. The difficulty with
using such excitation sources is that they are often variable and
distributed over a wide area of the structure making these inputs
almost impossible to measure. The variable nature of these signals
requires robust data normalization procedures to be employed in an
effort to determine that the change in the measured data is the result
of damage as opposed to changing operational and environmental
conditions. Also, there is no control over the excitation source, and
it may not excite the type of system response useful for identifying
damage at an early stage. As an alternative, a sensing system can be
designed to provide a local excitation tailored to the damage detection
process. Piezoelectric materials are being used for such active sensing
systems. Because these materials produce an electrical charge when
deformed, they can be used as dynamic strain gauges. Conversely, the
same materials can also be used as actuators because a mechanical
strain is produced when an electrical field is applied to the patch.
This material can exert small predefined excitation forces into the
structure on a local level. The use of a known and repeatable input
makes it much easier to process the measured response signal for damage
detection. For instance, by exciting the structure in an ultrasonic
frequency range, the sensing system can focus on monitoring changes of
structural properties with minimum interference from variability in
traffic loading, which tend to be low-frequency in nature. Faculty and
staff from the LANL/UCSD Engineering Institute (Prof. Lanza di Scalea
and Dr. Gyuhae Park, as well as the authors) are among a small group of
researchers in the U.S. leading the development of these active sensing
approaches for civil engineering infrastructure damage assessment.
From the data interrogation approach, researchers have recognized
that the damage detection process is fundamentally a problem in
statistical pattern recognition. Basically, the damage detection
process requires one to identify changes in the pattern of the sensor
readings that result from damage. Therefore, the extensive sets of
machine learning and pattern recognition tools developed for
applications such a speech pattern recognition and credit card fraud
detection are also directly applicable to the damage detection problem.
The adaptation and further development of such algorithms for the data
interrogation part of the damage detection process has been pioneered
by researchers at the Engineering Institute (Prof. Hoon Sohn of the
Korean Advanced Institute of Science and Technology while a staff
member at Los Alamos) working in conjunction with faculty from the
University of Sheffield in the U.K. (Prof. Keith Worden). Such
algorithms are now being embedded on the microprocessors that are
integrated into the wireless sensing nodes in an effort to distribute
the damage assessment process to the individual sensor nodes. The
combination of this more ubiquitous sensing along with more robust data
interrogation algorithms is giving engineers the hope that in the not
too distant future continuous monitoring of damage initiation and
accumulation in civil infrastructure will one day be a reality.
(3) What are the barriers to transitioning SHM/DP technologies from
research to practice?
Other than in a very few areas such as the rotating machinery
industry, SHM/DP technologies are still largely confined to laboratory
demonstrations and not to industrial practice, despite the fact that
SHM/DP technology traces its modern roots to the 1970s and 1980s, when
the offshore oil, civil engineering, and aerospace communities first
began exploring it. These technologies grew out of the more mature
field of nondestructive evaluation and inspection, and it was motivated
by engineers' desire to detect damage in an online manner (i.e., while
the structure is in operational service) on a more global scale. There
are several reasons why SHM/DP has not made the transition from
research to practice, some technical and others not. One of the primary
technical difficulties in shaping an SHM/DP strategy for something as
complex as a bridge is the wide range of length and time scales over
which different forms of damage can initiate and proceed. Fatigue
cracking or stress corrosion cracking initiates on a very small
(micrometer-level) length scale that is most probably detected only by
a nondestructive inspection technique like ultrasonic inspection, which
is very difficult to implement in an online, cost-efficient manner for
large-scale structures. Also, depending upon loading and environmental
conditions, cracks grow on both very slow (initially; measured over
months or years in many cases) and very fast (near failure; measured
over seconds) time scales. Furthermore, complex structures such as
bridges can have a great diversity of degradation mechanisms (e.g.,
steel fatigue, concrete cracking, scour of soil around bridge piers,
corrosion) that may all be occurring simultaneously, each on its own
length and time scales. Such wide ranges in length and time demand very
different sensing and data interpretation strategies, all of which make
any sort of ``one size fits all'' SHM/DP strategy highly unlikely.
A second challenge is that most SHM/DP technologies are being
developed in research-oriented environments (such as a university)
where there is limited ability to test the technologies on actual full-
scale structures in the field. A consequence of this limitation is that
we in general have very little knowledge about the long-term durability
of sensing networks that could be deployed as part of an SHM/DP
strategy. The only experience with long-term sensor system deployment
and monitoring of bridges comes from the relatively few bridges that
are instrumented for seismic monitoring as part of the California
Strong Motion Instrumentation Program. These arrays have provided the
community with bridge (and other infrastructural) response to
earthquake ground motion, which has served to significantly advance the
fields of seismic retrofitting and new design paradigms. However, these
arrays were not specifically designed or deployed for damage
identification and monitoring studies. In addition, there are very few
out-of-service bridges still standing that can serve as test beds for
destructive testing on which researchers can validate their SHM/DP
strategies under realistic operational and environmental scenarios.
However, we are greatly encouraged by the FHWA's ``Long-Term Bridge
Performance Program,'' as described by Dr. Steven Chase in a keynote
lecture at the 6tn International Workshop on Structural Health
Monitoring at Stanford University, on September 11-13, 2007. This
program plans to develop the necessary long-term test beds needed to
validate new SHM technology.
Moreover, the funding levels normally accorded such researchers is
not sufficient to sustain tests long enough to establish true proof-of-
concept. We applaud some of the state transportation agencies with whom
we or our immediate colleagues have worked, such as CALTRANS and the
New Mexico Department of Transportation, for their forward-thinking
efforts in funding and/or facilitating research and development in SHM/
DP technologies for bridges. Overall, however, the funding levels that
are typically allocated to such projects are well short of what is
required. The model used by most funding agencies--the single Principal
Investigator three-year award--typically amounts to between $250,000 to
$300,000 total funds invested in the complete development, testing, and
validation of the given technology. This funding level is not
sufficient to transition a proof-of-concept demonstration to a
reliable, field-deployable system. Moreover, these single-investigator
funding levels are not nearly sufficient to integrate the many
components required by the multi-disciplinary nature of SHM/DP
technology development.
As we alluded previously, there are non-technical challenges as
well. Traditionally, many universities are not really established to
support the kinds of large multi-disciplinary efforts required to bring
such a technology to bear. Universities generally offer relatively
narrowly-defined degrees (e.g., electrical engineering, mechanical
engineering, etc.), when in fact the person optimally trained to
develop SHM/DP technologies should be trained in aspects of many such
degree programs. Additionally, universities also do not generally tend
to encourage or reward the professoriate for undertaking such projects.
Promotion and tenure is typically based on individual merit, not the
success of teaming arrangements, particularly for junior faculty
seeking tenure. Such a system does not encourage faculty to work
together to solve complex problems or develop complex technologies that
demand multi-disciplinary contributions. Clearly these are cultural
issues that exist and must be addressed at the university level, and we
recognize and commend the Committee for its efforts to promote
interdisciplinary research, particularly via the National Science
Foundation. The Engineering Institute has attempted to tackle some of
these barriers by offering graduate degrees at the University of
California San Diego that require course work in several departments
and by funding graduate research projects that span several
departments. It is our hope that such efforts will be replicated on a
broader scale, and further encourage the university community to
deconstruct these 'silo' models and to seek partnering opportunities
not only across departments but also with each other in order to meet
the multi-disciplinary needs of tomorrow's technologist.
(4) How does the United States compare to other countries with respect
to implementing SHM/DP technologies in infrastructure health
management?
A number of Asian countries have taken an increasingly proactive
approach to infrastructure assessment and management. The Hong Kong
(China) government, through the Highways Department of Hong Kong, has
implemented a large-scale monitoring program on the Tsing Ma suspension
bridge (and subsequently on another suspension bridge in the vicinity)
whereby real-time data streams of bridge vibration/deflection, load,
cable forces, wind speed, temperature, and visual camera images are
synthesized in a master control center from which bridge management
decisions regarding traffic patterns, speed regulations, load limits,
and other such similar performance variables are continuously updated.
Data are also being collected for long-term research efforts to
identify damage detection and tracking algorithms that correlate with
normal visual inspections and subsequent maintenance actions so that
SHM/DP technologies may be field-validated over long times. The cost of
this system has been reported as somewhere between $15-20 million. Even
with this significant investment it is not clear that these researchers
have a robust damage detection strategy in place. However, by
allocating the resources for this system and by making a long-term
commitment to acquire and analyze the data obtained, these researchers
are better positioned to learn how to make accurate damage assessments.
This project is just one of many significant bridge monitoring systems
being deployed in China that we have heard about at international
conferences on structural health monitoring. We are unaware of similar
bridge monitoring projects of this magnitude in the U.S.
In Seoul, Korea, the Seongsu Bridge collapsed suddenly in 1994 due
to a structural failure, killing 32 people. As a result, the Korean
government mandated that the infrastructure construction companies must
provide monitoring systems for that infrastructure. Currently, these
monitoring systems have only a limited number of sensors, and it is
questionable if they will provide the necessary local information
needed to identify local damage at its onset.
We are also aware of other bridges in Thailand, Singapore, Taiwan,
and Japan that have installed monitoring systems. Some of these
monitoring systems have been purchased from U.S. companies such as
Kinemetrics, Inc. in Pasadena, CA. However, to the best of our
knowledge this company has not sold a system for monitoring a bridge in
the U.S. Although there have been numerous large-scale SHM research
projects on bridges in Europe, we are not aware of any long-term
instrumentation projects in Europe that are as extensive as the ones
being undertaken in Asia. There are companies in Europe such as VCE
Holding in Vienna, Austria that specialize in monitoring civil
engineering infrastructure. It was recently reported that they have
done measurements on over 1,100 bridges in Europe.\8\ To paraphrase a
quote from a recent keynote lecture on bridge structural health
monitoring by a representative of this company, ``Monitored bridges and
buildings in Europe and Asia are considered intelligent structures
while monitored bridges and buildings in the U.S. are considered
suspect.''
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\8\ H. Wenzel, ``SHM at the Civil Infrastructure: Applications,
Recent Progress and Future Demands,'' Keynote lecture, 6th
International Workshop on Structural Health Monitoring, Stanford,
California, September 11-13, 2007.
(5) What are elements that the U.S. Government should consider as it
crafts an investment plan, both near-term and longer-term, for
promoting the development of SHM/DP technologies, and facilitating
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their transition to practice for infrastructure health management?
We begin by strongly encouraging the government, through its
various funding agencies such as the National Science Foundation, the
Federal Highways Administration, Defense Advanced Research Projects
Agency, DOE, and the various DOD research offices, to substantially
increase its emphasis on investment in SHM/DP technology development
with specific attention to field deployment of test systems. Even more
importantly, the share of this investment earmarked for development of
basic science and engineering concepts, where the time to maturity is
in the 5-10 year range, should be brought into balance with the much
shorter time horizons associated with industrial times-to-market,
typically 6-18 months. We believe the current funding profile that
heavily weights the shorter time horizons exacerbates the technical
challenges presented above. That is, there is inadequate funding to do
exactly the kind of longer-term exploratory field deployments needed to
transition the SHM/DP technology into practice. These short industrial
times-to-market certainly have their place in infrastructure health
management. Through SBIR and STTR small business programs, agencies can
fund small studies on more mature technologies (for example, a new kind
of sensor already prototyped) where proof-of-concept requirements are
in line with these short industry time scales and can solve certain
specific problems already identified.
We believe that a sound renewed commitment to investing in
fundamental science and engineering, particularly where multiple
disciplines are integrated to solve problems at the systems level, can
ensure a strong, balanced research investment portfolio that optimizes
the return on that investment. The Committee has led by example on this
front, setting forth an aggressive vision for a ten-year doubling of
the NSF budget. Particularly given such an appropriate infusion of
resources, federal funding agencies can easily be tasked with such a
mission and put into a position of being encouraged and rewarded for
cooperating to pool resources as necessary in the short-term in order
to promote these multi-disciplinary field deployments.
We urge that the engineering/technical community work proactively
with policy-makers to develop, fund, and execute a comprehensive
research, development, and transition plan that engages all technology
developers with a reasonable balance of academic, industry, national
laboratories and government partners.
More specifically, we would like to reiterate our support of the
FHWA's Long-Term Bridge Performance Program. Such test beds are
absolutely essential to the further development, validation and field
deployment of SHM technology as it is applied to bridge monitoring. We
further recommend that funds are made available for each state
transportation department to support the deployment of at least one
large-scale, long-term monitoring system on a bridge that is of most
concern. This funding must also provide for long-term management and
analysis of the data obtained from such a monitoring system. Ideally,
as part of these studies the more advanced structural health monitoring
concepts will be directly compared to traditional inspection techniques
over a long period of time. Such comparisons are necessary to validate
the SHM methods and to show that these methods can provide a higher
fidelity of damage detection and quantification than the current visual
inspection methods.
We recommend that policy-makers consider the significant amount of
technology components being developed at universities, national
laboratories and industry that are directly applicable to the bridge
health monitoring problem. However, these technologies must be
integrated in a systematic manner to best address the SHM problem as it
applies to bridge structures as well as to all types of civilian and
defense infrastructure. When technologies from all these sources are
integrated though multi-disciplinary research teams such as the one
formed by LANL and UCSD, solutions to the complex problem of structural
health monitoring can be more rapidly advanced and deployed.
Finally, although this document has emphasized the need for more
research aimed at transitioning SHM technology from research to
practice, we strongly urge policy-makers to continue to promote formal
education innovation in this field. U.S. universities have a long
history of being the best at training the technical specialists, and
there will be always be a need for such specialists. However, for the
U.S. to retain its technical advantage in the global economy, we must
also be able to educate a new generation of multi-disciplinary
engineers that can integrate diverse technologies to solve complex
problems of national importance. In addition, technology leaders of the
future will also have to be much more multi-disciplinary than in the
past. A key aspect of The LANL/UCSD Engineering Institute is its
proactive efforts to develop such a new multi-disciplinary degree
program that focuses on training the next generation of engineers in
SHM/DP and on training the next generation of technology leaders. It is
our position that such formal multi-disciplinary education programs
(not just multi-disciplinary research) need to be promoted as a
national educational priority.
Thank you again for this opportunity to submit testimony to the
Committee, and we hope that we can serve as a resource to the Committee
as it considers these and related issues of critical importance to our
nation's infrastructure. The faculty, students, and staff of the LANL/
UCSD Engineering Institute looks forward to continued interactions with
policy-makers, Federal and State Government agencies, and private
industry that will further promote and deploy SHM technology on all
types of aerospace, civil, and mechanical infrastructure.
Statement of Larry W. Frevert
President
American Public Works Association
Mr. Chairman and Members of the House Committee on Science &
Technology, thank you for the opportunity to submit testimony for the
hearing, Bridge Safety: Next Steps to Protect the Nation's Critical
Infrastructure. My name is Larry Frevert, President of the American
Public Works Association (APWA). I submit this statement today on
behalf of the more than 29,000 public works professionals who are
members of APWA, including our nearly 2,000 public agency members.
APWA is an organization dedicated to providing public works
infrastructure and services to millions of people in rural and urban
communities, both small and large. Working in the public interest, our
members design, build, operate and maintain our vast transportation
network, as well as other key infrastructure assets essential to our
nation's economy and way of life.
We join with others in expressing our deepest sympathy to everyone
affected by the I-35W bridge collapse in Minneapolis on August 1. We
remain saddened by this tragedy and continue to extend our support to
local, State and federal officials working on recovery and rebuilding.
The tragic failure of the I-35W bridge is a stark reminder of the
importance of public infrastructure to the daily lives of all people
and to the welfare and safety of every community. But this essential
public asset is aging and deteriorating. It is suffering the effects of
chronic under-investment and is in critical need of funding for
maintenance, repair and improvement.
Our nation's highway bridges are no exception. The average span
currently is more than 40 years old. More than one in every four is
rated structurally deficient or functionally obsolete and in need of
repair, improvement or replacement. Of the more than 594,000 publicly-
owned bridges on which we depend for personal mobility and movement of
freight, more than 158,000 are rated deficient, with more than 77,700
classified as structurally deficient and more than 80,600 as
functionally obsolete.
Local governments own in excess of 300,000 bridges, more than half
of publicly-owned bridges in the U.S. Of the total local inventory
nationwide, 29 percent is rated structurally deficient or functionally
obsolete.
Standards have been in place since the early 1970s requiring safety
inspections every two years for all bridges greater than 20 feet in
length on all public roads. Some bridges may be subject to more
frequent inspections, and some structures in very good condition may
receive an exemption from the two-year cycle and be inspected once
every four years. These inspections, carried out by qualified
inspectors, collect data on the condition and composition of bridges.
Structurally deficient bridges are characterized by deteriorated
conditions of significant bridge elements and reduced load-carrying
capacity. Functional obsolescence results from changing traffic demands
on the structure and is a function of the geometrics of the bridge not
meeting current design standards. Neither designation indicates a
bridge is unsafe. But they do indicate a need for repair, improvement
or replacement.
We cannot ignore the under-investment in bridge maintenance,
rehabilitation and replacement. It is a major contributing factor
undermining efforts to adequately address deficiencies. Nationwide, the
backlog of bridge investment needs is now estimated to total $65.2
billion.
As a nation, we are failing to meet the needs of a transportation
system increasingly overburdened by rising travel, a growing population
and more freight. Additional traffic volumes and heavier loads are
placing ever greater stress on bridges often designed for lighter
loads. The U.S. Department of Transportation reports that the funding
backlog could be invested immediately in a cost-beneficial fashion to
replace or otherwise address currently existing bridge deficiencies.
Local governments' ability to fund necessary bridge improvements
has eroded significantly over the years. They have limited financial
means to adequately address deficiencies and typically do not have the
capacity to do major repairs or capital work on the magnitude of a
bridge replacement without funding support.
Sharp increases in the costs of construction materials and supplies
in the past few years are compounding the funding challenge for local
governments. In Washington State for example, escalating material and
supply costs and one of the largest construction programs in the Nation
have had a severe impact on delivering local agency projects. It is not
unusual to take 10 years or more from the time funding can be secured
and replacement done. And with the recent industry cost index
increases, the gap is growing and will continue to grow.
Immediate action to increase investment is crucial to accelerating
local bridge repair and replacement programs. Most bridges on local
roads were either built to older standards or are so old they are in
urgent need of repair or replacement. It is not uncommon that bridges
have gone for years, even decades, without the appropriate action to
repair or replace, due to lack of funds. This is particularly true in
more rural areas.
In many cases, locally-owned bridges were often designed to carry
traffic volumes and loads less than present conditions demand. As
congestion increases on the Interstate System and state highways, local
roads become diversion routes, supporting ever increasing levels of
usage. Freight volumes, too, have increased faster than general-purpose
traffic, adding demands on all parts of the system. Automobile
technology allowing for greater speeds has made many bridge geometrics
substandard.
Deficient bridges are rated, prioritized and repaired or replaced
as funding is available. When funding is insufficient, deferred
maintenance, increased inspections, weight limits and closures are
often the only options.
APWA has been and will continue to be an advocate for the
development of public policies which ensure the safe and efficient
management and operation of our public infrastructure. As Congress
considers the needs of our bridge system, we urge you to consider the
following recommendations.
APWA supports a determined, comprehensive national effort to
increase investment to eliminate the bridge funding backlog needed to
repair, rehabilitate and replace all publicly owned bridges--including
local bridges--as part of a zero bridge deficiencies goal. Such an
effort, however, should not stop there. It needs sustained and
sustainable funding to ensure ongoing system preservation and
maintenance at a level necessary to prevent future deficiencies of all
publicly-owned bridges.
APWA also supports updating bridge inspection standards and
strengthening data collection and reporting procedures; evaluating
active bridge monitoring systems; and strengthening inspector
qualifications and training and inspection technologies, research and
procedures for all publicly-owned bridges, including those on our local
system. We believe that a program to strengthen research, technology,
procedures and standards must be supported by full federal funding
necessary to carry out and sustain it.
In conclusion, our nation's bridge system is aging, deteriorating
and suffering the effects of decades of under-investment. The result is
the unacceptably high levels of deficiencies we see today. APWA
believes that working together in partnership with local, State,
federal and private sector partners, we can and must take immediate
action to address our bridge needs. But it will take funding and
leadership. Increased investment to repair or replace deficient bridges
is vital to achieve a safer and more efficient transportation network.
A strengthened inspection program can help ensure that we make wise
investments to maintain and preserve all bridges.
Mr. Chairman, we thank you for holding this hearing and are
especially grateful to you and Committee Members for the opportunity to
submit this statement. APWA and our members stand ready to assist you
and the Committee as we move forward to address our nation's bridge
needs.