Long-Term Bridge Performance Program

Focus Group Participation in the LTBP Programs

The Federal Highway Administration (FHWA) is partnering with stakeholders in order to identify critical performance issues and obtain access to the information and data that is needed to improve the long-term performance of bridge systems. Since the program cannot be a one size fits all approach, and to avoid additional burdens on highway agencies, a series of focus group meetings across a number of geographically distributed States was conducted. The focus groups represent owners of a geographically, economically, and environmentally diverse cross-section of State highway agencies, and they represent a majority of the custodians of the national bridge inventory.

Six regions were designated across the continental United States and an initial list of candidate State highway agencies were selected for each region. Representative States were then visited and participated in focus groups using a customized interview questioner. The State departments of transportation (DOTs) that participated in these focus groups included: Alabama, California, Florida, Illinois, Iowa, Kansas, Maine, Montana, New Jersey, New York, Ohio, Oregon, Texas, Utah, and Virginia. State DOTs input were attained and consolidated to help ensure that the LTBP program will have necessary information to identify bridge performance issues and topics.

Identification of Bridge Performance Study Topics

Through information gleaned from the stakeholder interviews and literature review, a proposed series of study topics was identified. The table below lists these general study topics. Additional topics and refinement of the proposed topics is being considered as additional input is gathered from stakeholders.

A cursory literature review on each of the identified study topics was completed, providing a brief summary of the state of practice, previous related research, and identification of remaining questions that might be addressed under the LTBP program. By documenting fundamental research questions to be addressed, the LTBP program identified the range of documentation, inspection, testing, instrumentation and monitoring necessary to advance the state of knowledge in the topic area of interest. Ultimately, this would be used to identify specific data needs and subsequently to specify procedures and protocols for obtaining the required or desired information.

For each Study Topic, a series of key questions was posed to elucidate the knowledge gaps identified and direct the development of appropriate experiments to address those questions. For each question, one or more hypotheses were posed to describe the anticipated outcomes of the experiments, and then the data required to address and evaluate each hypothesis was formulated. Such data sources would include combinations of already available highway network and structure-specific inventory and condition information, as well as data to be specifically generated under LTBP through field observation and testing or data mining from internal or external sources. Thus, the generally Study Topics are refined into a series of experiments and specific data needs identified to support those experiments.

The goal is to establish a series of experiments and to select representative samples of the bridge population for field evaluation and monitoring over the program period. This is to gather the necessary quantitative data to answer the questions posed and develop and refine criteria and models for bridge performance. It is desired that the information developed under this program address all aspects of performance of a typical bridge, ranging from structural condition and stability to functionality. The intent is for the information gleaned to be applicable to a broad range of structures throughout the United States and of direct benefit to the bridge maintenance and management personnel responsible for their care.

Long-Term Bridge Performance Suggested Study Topics