FRP BARS FOR BRIDGES

To overcome corrosion-related problems, one solution is to replace steel reinforcement with fiber-reinforced polymer (FRP) reinforcement. This article describes innovative field applications of FRP bars as reinforcement for the concrete decks of four bridges in North America. The main objective of these projects is to implement the technology and design of FRP reinforcing bars and to demonstrate their ability to meet all bridge construction requirements. The short- and long-term performance of FRP reinforcement is assessed. Based on the construction details and the results of field tests, long-term monitoring and periodical visual inspection, it can be concluded that: (1) no obstacles to construction were encountered due to the use of the FRP bars; (2) the serviceability performance of the concrete deck slabs reinforced with FRP bars was very similar to slabs reinforced with steel bars in terms of strain, cracking and deflection; (3) the maximum tensile strain in the FRP bars was 18 microstrain during all testing, which was less than 0.16% of the ultimate strain of the material; (4) under service conditions, due to temperature extremes, the measured peak strains in the FRP bars was about 3-4% of the ultimate strain; (5) FRP-reinforced bridges performed well under severe service conditions; and (6) these field applications can contribute significantly to establishing an optimum design procedure for concrete deck slabs reinforced with FRP bars. The overall findings suggest that FRP-reinforced concrete decks can compete with concrete bridges reinforced with steel under real service conditions.