Below is the uncorrected machine-read text of this chapter, intended to provide our own search engines and external engines with highly rich, chapter-representative searchable text of each book. Because it is UNCORRECTED material, please consider the following text as a useful but insufficient proxy for the authoritative book pages.
7 PREPUBLICATION COPYâUncorrected Proofs 1. INTRODUCTION The Innovative Bridge Research and Construction (IBRC) program was created by Congress in the 1998 Transportation Equity Act for the 21st Century (TEA-21). TEA-21 authorized the federal highway and transit programs for 1998 to 2003. (Continuing resolutions of Congress later extended the provisions of the Act, including IBRC, to 2005.) The purpose of IBRC was to demonstrate the application of innovative materials and technologies in the construction and repair of highway bridges. The program provided funding for part of the costs of approximately 400 projects from 1999 to 2005 (FHWA n.d.a, HDR 2013). Total funding made available by Congress under the program was $128.7 million (as determined by authorized funding and annual obligation limitations imposed on the federal-aid highway program) (FHWA 2008, 7). Materials used included fiber-reinforced polymer (FRP) composites, high-performance steel (HPS), advanced concrete materials, and corrosion-resistant reinforcing bar (rebar). Projects also demonstrated accelerated bridge construction techniques. Historically, technical innovation in materials and construction methods has allowed savings in construction and maintenance costs, improved durability and reliability, and extended the service life of highway infrastructure. However, highway agencies face obstacles to the adoption of innovations. Contracting and budgeting practices may disfavor designs with higher initial cost but lower life-cycle cost and designs that reduce user costs (resulting from delay and crash risk during construction) at the expense of higher agency costs. Contracting regulations can discourage use of proprietary materials or processes.1 Early projects that use new technology can have higher costs because designers and contractors must learn how to use the new materials and methods and the lack of experience entails a risk of errors or disappointing results. Owners and the construction industry may resist change due to its inherent risks. The IBRC program provided an incentive for highway agencies to overcome these obstacles to gain the benefits of innovation. 1 23 CFR 635.411, known as the proprietary and patented products rule, prohibits state highway agencies from requiring use of a patented or proprietary material, specification, or process except in certain special circumstances.
8 PREPUBLICATION COPYâUncorrected Proofs As it was directed by Congress in Section 1422 of the FAST Act, the 2015 federal transportation authorization legislation, the U.S. Department of Transportation commissioned TRB to conduct a study of the performance of bridges that received funding through the IBRC program. To perform the study, TRB formed the Committee for the Study on Performance of Bridges, composed of engineers from universities, highway agencies, and industry with expertise in the materials and technologies that were employed in the bridges. STUDY CHARGE The committeeâs charge (see Box 1.1), which was specified by Congress in the FAST Act, asks it to undertake four tasks: 1. Analysis of the performance of bridges that received IBRC funding in meeting the goals of the program. 2. Analysis of the utility, compared to conventional materials and technologies, of the innovative materials and technologies used in IBRC projects in meeting needs for a sustainable and low life- cycle-cost transportation system. 3. Recommendations to Congress on how the installed and life-cycle costs of bridges could be reduced through the use of innovative materials and technologies. 4. A summary of any additional research that may be needed to further evaluate innovative approaches to reducing the installed and life-cycle costs of highway bridges. The seven goals of the IBRC program, as defined in TEA-21, were to develop: Cost-effective, new, innovative materials for highway bridge applications. Methods for reducing maintenance and life-cycle costs of bridges. Construction techniques to increase safety and reduce construction time and traffic congestion. Design criteria for innovative products and materials. Techniques to separate vehicle and pedestrian traffic from railroad traffic.
9 PREPUBLICATION COPYâUncorrected Proofs Structures that will withstand natural disasters. Nondestructive evaluation technologies and techniques. SOURCES OF INFORMATION A complete response to the committeeâs first taskâdetermining whether the IBRC projects were successful in meeting the goals of the programârequires two kinds of evidence: Information about how the experience of the IBRC projects affected highway agency practices: whether the technologies used in the stateâs IBRC projects were incorporated in regular practice, whether experience with the IBRC projects influenced present use, and whether the IBRC experience stimulated development of standards and specifications for the technology. Data on the performance over time of the IBRC bridges, as evidence of the benefits of the IBRC technologies with respect to durability; construction, maintenance, and user costs; and service life. Evidence from the IBRC projects and also from evaluations of other experience with the technologies used in the projects is relevant to the second taskâanalysis of the utility of the IBRC technologies compared with conventional methods. The information available to the committee was incomplete. The IBRC program did not require highway agencies to conduct any special monitoring or evaluation of the performance of the bridges that received funding or to document the effect of new technology on life-cycle cost. Routine bridge inspections generally will not provide specific and detailed data on the performance of the features of the IBRC bridges that embody the new technology. Bridge construction that received IBRC funding occurred less than 20 years ago, an inadequate time span for a full comparison of the durability of IBRC and conventional materials. However, any cases in which a material performed well below expectations would be observable, and a robust monitoring program (that collected performance data beyond routine visual inspection) might have been able to detect any early differences in performance, for example, signs of deterioration of reinforcing materials in concrete.
10 PREPUBLICATION COPYâUncorrected Proofs Finally, schedule and budget constraints did not allow the committee to obtain current information on all IBRC bridges or to obtain condition information other than that readily available in bridge inspection records. The following subsections describe the sources the committee used to respond to its charge. The information from these sources is presented in later chapters. FHWA Project Lists The Federal Highway Administration (FHWA) provided the committee with a list of 324 projects that received IBRC funding, indicating the state, the innovative material or technology that qualified the project for the program, the general location of the project, a truncated description of the project, and an identifying project number (FHWA n.d.a). National Bridge Inventory numbers and exact locations were not recorded. This list appears to omit projects funded in the final year of the program, 2005. A second list provided by FHWA shows amounts of federal funds obligated and spent on each of 367 IBRC projects, identified by project numbers in a different format from those in the first list (FHWA n.d.b). A list compiled by HDR, Inc. (see the following section) includes 77 projects awarded funds in 2005; some of these may not have been carried out or may have been extensions of earlier projects. Because of the lack of a common system of project identification, it was not possible to consistently match projects across lists. Consequently, the committee did not have a complete and authoritative list of IBRC projects. HDR Report In 2013, an FHWA contractor compiled information for bridge projects that received funds from the IBRC program and from a similar program (Innovative Bridge Research and Deployment [IBRD] program) established in 2006 (HDR 2013). The contractorâs report is based on information received from the state highway agencies that conducted projects in the two programs. It includes a two-page summary of each project for which information was received, including a brief project description, the innovative technology employed, IBRC or IBRD funds awarded, and the highway agencyâs identification of positive and negative results, obstacles to implementing the technology, lessons learned, and reuse of or plans to
11 PREPUBLICATION COPYâUncorrected Proofs reuse the technology in other projects. Assessments of results are qualitative in nature. No data on performance over time were collected. The report also includes case studies describing 30 projects in detail. The case studies do not contain performance information, although some results of laboratory testing of materials are reported. Four of the case studies include limited information on cost savings from the innovative technology, compared with conventional practice. Finally, HDR compiled a library of assessments of the projects that the states or others had carried out. Some highway agencies did not provide information for the HDR report. State Interviews TRB engaged a consultant to conduct interviews, under the direction of the committee, with state highway agency officials in 10 states that had been active participants in the IBRC program and had completed IBRC projects using diverse technologies (see Table 1.1). The interviews were to obtain information about the performance of the statesâ IBRC bridges and the influence of the statesâ experience participating in the IBRC on their subsequent use of the IBRC technologies. The interview topics included the following: Topics relevant to the committeeâs first task (to analyze the performance of the IBRC bridges in meeting the programâs goals): - Extent of use today of the technologies that were used in the stateâs IBRC projects. - Existence of specifications or standards for use of the technologies. - Reasons for not adopting technologies that were tried in the stateâs IBRC projects but are not in use today. - Influence of experience with the IBRC projects on present use (or nonuse) of the technologies. - Effect of training requirements on the stateâs decisions about adopting IBRC technologies. - Effect of availability of standards and specifications on use of the technologies. Topics relevant to the committeeâs second task (to analyze the utility of the IBRC technologies in meeting needs for a sustainable and low life-cycle-cost transportation system):
12 PREPUBLICATION COPYâUncorrected Proofs - Benefit of the IBRC technologies the state now uses, compared with previous practice. - Results of quantitative evaluations of the benefits. - Available data on performance and costs over time of the stateâs IBRC bridges. Topics relevant to the committeeâs third and fourth tasks (how life-cycle costs of bridges could be reduced through the use of innovative materials and technologies; research needed to further evaluate innovative technologies to reduce the installed and life-cycle costs of highway bridges): - Obstacles to the stateâs use of promising IBRC technologies and actions needed to overcome them. - Methods of identifying and evaluating innovations in the stateâs bridge program. - State officialsâ views on research needs to develop methods to reduce the costs of bridges. - State officialsâ views on the possible value of programs similar to IBRC in the future. TABLE 1.1 Case Study States: IBRC Technologies Used and Grant Amounts Received State Number of IBRC Projects Employing Each Technology Category Total Projectsb IBRC Grants Received ($ millions) Concrete FRP Corrosion Control HPS ABC Othera California 1 11 3 2 13 3.4 Iowa 6 8 1 1 2 16 3.4 Michigan 2 3 4 9 1.8 Missouri 5 5 3 2 1 16 2.1 New Hampshire 7 2 2 1 2 10 2.8 New York 3 14 3 2 3 21 2.9 Pennsylvania 7 2 2 1 1 13 2.6 Texas 2 5 4 5 2 18 4.3 Virginia 9 8 3 19 6.4 Washington 2 5 1 2 1 8 3.0 HPS: high-performance steel; FRP: fiber-reinforced polymer; ABC: accelerated bridge construction. SOURCES: numbers of projects by technologyâcommitteeâs classification of projects based on the FHWA (FHWA n.d.a) and HDR project lists (HDR 2013); grants received (HDR 2013). a Includes glue-laminated hardwood deck panels (PA), monitoring and instrumentation (CA), graffiti- resistant coating (TX), and a project for which complete information was not available (TX). b Some projects employed technologies in more than one category; therefore rows do not necessarily sum to the total number of projects in a state. Views of Supplier Industry Representatives The committee invited representatives from associations of the steel bridges, concrete bridges, and composite materials industries to comment on the committeeâs charge in presentations at a public
13 PREPUBLICATION COPYâUncorrected Proofs meeting. Specifically, the representatives were asked to comment, from the standpoint of their respective industries, on the success of the IBRC program in promoting innovation, the utility of the materials and technologies demonstrated in the IBRC projects, current opportunities to reduce the life-cycle cost of bridges through new technologies, and research needed to evaluate innovative approaches. Published Evaluation Research Most of the innovative materials and technologies in the IBRC projects are by now widely used, and evaluations have been published of their performance and costs in projects other than IBRC projects. To supplement the limited information available about the performance of the IBRC projects, the committee consulted published evaluations of the materials and technologies in other projects as a basis for conclusions on its second task, to analyze the utility of the IBRC materials and technologies compared with conventional methods. The committee also noted gaps in the published record of performance of some technologies. AASHTO Survey At the request of the committee, the American Association of State Highway and Transportation Officials (AASHTO) included two questions in its 2018 AASHTO Committee on Bridges and Structures Annual State Bridge Engineers Survey, sent to all state highway agencies. For each of the IBRC technologies, agencies were asked two questions: âIs the technology currently in use in your state?â and âHave you adopted special provisions or specifications related to this technology?â Responses were received from 40 states, although not all states answered all questions. ORGANIZATION OF THE REPORT In the remainder of this report, Chapter 2 describes the administration of the IBRC program and the projects that it funded. Chapter 3 describes state highway agenciesâ experiences with the program, with respect to the impact of the program on their adoption of innovations in bridge construction. Chapter 4
14 PREPUBLICATION COPYâUncorrected Proofs summarizes the available information on the performance of the IBRC bridges and the utility of the IBRC materials and technologies. Chapter 5 presents the committee's conclusions on the performance of the IBRC projects in meeting the goals of the program, the utility of the IBRC technologies, and opportunities to reduce life-cycle costs with new technology; and recommendations on research needs and on federal actions to promote innovation in highway bridge construction. ========================================================================== Box 1.1 Study on Performance of Bridges Statement of Task An ad hoc committee will conduct a study on the performance of bridges that received funding under the innovative bridge research and construction program under section 503(b) of title 23, United States Code (as in effect on the day before the date of enactment of Public Law 109-59; 119 Stat. 1144) in meeting the goals of that program, which included: (1) the development of new, cost-effective, innovative materials for highway bridge applications; (2) the reduction of maintenance costs and life-cycle costs of bridges, including the costs of new construction, replacement, or rehabilitation of deficient bridges; (3) the development of construction techniques to increase safety and reduce construction time and traffic congestion; (4) the development of engineering design criteria for innovative products and materials for use in highway bridges and structures; (5) the development of cost-effective and innovative techniques to separate vehicle and pedestrian traffic from railroad traffic; (6) the development of highway bridges and structures that will withstand natural disasters, including alternative processes for the seismic retrofit of bridges; and (7) the development of new nondestructive bridge evaluation technologies and techniques. The study will include: (1) an analysis of the performance of bridges that received funding under the program in meeting the goals described in items (1) through (7) above; (2) an analysis of the utility, compared to conventional materials and technologies, of each of the innovative materials and technologies used in projects for bridges under the program in meeting the needs of the United States in 2015 and in the future for a sustainable and low life-cycle cost transportation system; (3) recommendations to Congress on how the installed and life-cycle costs of bridges could be reduced through the use of innovative materials and technologies, including, as appropriate, any changes in the design and construction of bridges needed to maximize the cost reductions; and (4) a summary of any additional research that may be needed to further evaluate innovative approaches to reducing the installed and life-cycle costs of highway bridges. =========================================================================