Abstract
The use of glass-fiber plastic rebars (FRP) in structural applications subjected to aggressive service conditions is contingent upon their chemical durability, strength and property retention and dimensional stability for extended periods. This study examines the durability of fiber plastic rebars in concrete subjected to marine environments as in bridge substructural applications. Plastic rebars were exposed to several environments simulating different service conditions including moderate temperature effects and marine environments. The effect of different environments on the weight gain, rebar degradation and strength retention is presented for a reported exposure time of 140 days. Microscopic examination of the rebar cross section is also presented and compared to other experimental findings. It was found that the relative weight changes showed absorption mechanisms other than Fickian. Exposure to water maintained at ambient or moderately elevated temperatures did not result in significant property reduction or chemical degradation. However, exposure to environments simulating bridge substructures exposed to salt water resulted in fiber/matrix debonding and 15% strength loss for the exposure time reported. It is postulated that damage can occur through chemical interaction between the environment and the polymer matrix, glass fibers, or glass/polymer interface.
