Environmental durability of FRP to steel bonded joints in bridges

Paper i proceeding, 2016

Over the past four decades, fiber reinforced polymers (FRP) have been increasingly used for strengthening, repair and refurbishment of bridges. Although, the short-term behavior of FRP/steel bonded joints has been extensively studied, the subject of the durability has not been researched to the same degree. The lack of knowledge regarding the long-term performance presents a major obstacle to the growing application of FRPs in bridges. This work aims to investigate the effects of temperature, de-icing salt solutions and moisture on mechanical behavior of Carbon-FRP/steel joints. To realize this aim, forty CFRP/steel double lap shear specimens were aged in simulated de-icing salt solution and deionized water at 20°C and 45°C for up to eighteen months. The test results indicate a clear change of failure mode from cohesive to interfacial or interlaminar failure. Even though all the joints exhibited increasing load-bearing capacity during the first six months, the failure load of specimens aged at higher temperatures started to decline afterwards.