Long-Term Bridge Performance High Priority Bridge Performance Issues

CHAPTER 3. OTHER STAKEHOLDER INPUT

During the development phase of the LTBP Program and even prior to its start, FHWA and the research team sought input on critical aspects of bridge performance from key stakeholders and strived to maintain a continuing dialogue with members of the bridge community. An important element of that dialogue was the discussion of the bridge performance issues that the program could and should study. This dialogue was carried on in workshops and technical conference sessions devoted to long-term bridge performance, in briefings and discussions with bridge-related technical committees (for example, AASHTO and Transportation Research Board (TRB)), and in informal meetings with State transportation department bridge personnel.

FHWA LTBP WORKSHOP

In January 2007, FHWA, the National Science Foundation, and the University of Nevada—Reno cosponsored a workshop in Las Vegas to develop initial strategies and recommendations for implementing the LTBP Program. The workshop was attended by 46 professionals from State transportation departments, FHWA, industry, and academia. The purpose of the workshop was to gather the collective advice of these experts on how to implement the program and, most important, what they would suggest for the priorities for collection of bridge data. The workshop did not produce recommendations on performance issues to study but did generate a comprehensive list of data that could be collected on the properties and conditions of bridge elements and materials. The data needs identified are the subject of the upcoming FHWA report Identifying Long-Term Bridge Performance Data Needs. However, the lists of data recommended for collection clearly indicate an emphasis on the condition of the major elements of the bridge as a key issue.

FHWA SUBSTRUCTURES WORKSHOP

Based on the conclusions reached from the first 15 focus group meetings, several of the issues identified were ones in which geotechnical factors were of potential importance. These issues are the following:

• Direct, reliable, timely methods to measure scour.
  
  
• Scour countermeasures.
  
  
• Structure foundation types.
  
  
• Unknown foundation types.
  
  
• Bridge bearings (all types).
  
  
• Jointless structures (integral, semi-integral, continuous for live load).
  
  

Within this range of topics, FHWA research and management personnel were concerned that geotechnical, foundation, and substructure concerns may not have been adequately captured. Therefore, FHWA, as part of the LTBP initiative, hosted a Workshop to Identify Bridge Substructure Performance Issues in Orlando, FL, in March 2010. FHWA personnel, the LTBP Program research team, and approximately 30 invited attendees representing State transportation departments; FHWA headquarters, Federal aid, and Federal lands and research; academia; and consultants met to consider overall bridge performance and identify geotechnical performance metrics that may correspond to good and poor performance. Attendance at the workshop was by invitation from FHWA so that an effective mix of backgrounds and perspectives would be represented. The core of the workshop comprised breakout sessions to discuss three key elements of the program: bridge performance issues (affected by geotechnical factors); data needs and gaps (related to the issues identified); and tools, technology development, and monitoring (related to the data gaps).

Based on the brainstorming of the three groups and from the post-workshop discussions, the following short-term bridge performance priorities emerged (not in ranked order):

• Approach and bridge interface issues.
  
  
• Material degradation, corrosion, and deterioration issues.
  
  
• Mechanically stabilized earth (MSE) wall material degradation and assessment of wall integrity.
  
  
• Hydraulics, scour, and erosion.
  
  

From the results of this workshop and other available information, these issues are being considered and refined for inclusion in the LTBP Program list of study topics.^(4,5)

 

STATE LTBP COORDINATORS

FHWA has established an LTBP State Coordinators Group with one key bridge person from each State in the Nation, the Commonwealth of Puerto Rico, and the District of Columbia. The inaugural meeting of the LTBP State coordinators was held September 13–14, 2011, to familiarize the State representatives with the scope and goals of the program, summarize the anticipated role of the coordinators, and solicit their ideas and feedback on the conduct of the program and planning for the broader execution phase of the program. The list of high priority performance issues that was current at the time was presented to the group, and the coordinators endorsed the list.

One additional meeting was held with the Pennsylvania Department of Transportation in January 2012 to familiarize its representatives with the program and general findings of the development phase and solicit their comments. They identified some of the same issues as the focus group States, such as performance of deck joints and verification of the condition of embedded prestressing strands in prestressed concrete. They also identified the wear and tear that trucks used for fracking have caused to bridges along a specific highway in their State, early age cracking of high-performance concrete decks, and the uncertainty of how much that cracking might decrease the life of the deck as important issues to address.

TRB LTBP COMMITTEE

Under contract with the National Academy of Sciences, FHWA has coordinated with TRB to organize and facilitate a TRB LTBP Committee composed of members from government, industry, consultants, and academia to annually provide feedback on the progress of the LTBP Program and provide recommendations on strategies for the Program.

At the first meeting of the TRB LTBP Committee in November 2011, the members reviewed the high priority performance issues being recommended for study and subsequently informed FHWA of their concurrence with the proposed list.^(6,7)