State of the practice of FRP composites in highway bridges

Abstract

This case study presents the use of fiber reinforced polymer (FRP) composites in highway infrastructure. The state of current practice of FRP materials is established through a survey questionnaire and follow-up interviews with 46 responding transportation jurisdictions in North America (44 United States Departments of Transportation and 2 Canadian agencies) to identify current challenges requiring technical and administrative efforts to facilitate the employment of this promising construction material. FRP composites for infrastructure projects are generally satisfactory and promising. Most agencies have used FRP since 1996, although some agencies reveal pioneering endeavors in the early 1990s. The nature of construction projects determines whether FRP applications are experimental or a standard practice. The survey shows that CFRP-strengthening for upgrading bridge piers (primarily columns) is the most accepted standard practice, followed by GFRP-reinforced bridge decks. Challenges experienced by the responding agencies are detailed and analyzed. Various tests at material and structure levels are conducted to examine the performance of structural members constructed with FRP composites. Despite these endeavors, the long-term durability of in-situ FRP still requires additional research to generate technical data and to convince end-users. Lessons learned from sites are elaborated to assist practitioners who are interested in FRP-based projects. The majority of respondents state that more training is necessary to help understand the use of FRP composites in construction projects.