Degradation of Interfacial Behaviour Between AFRP and Concrete Under Sulfate Attack

Sulfate attack is a kind of salt corrosion which causes deterioration of concrete structural properties. For fiber-reinforced polymer (FRP) strengthened concrete structures, it is also one of the significant factors affecting the bond behaviour between FRP and concrete. In this study, the effect of sulfate attack on the bond behaviour of Aramid FRP (AFRP)-to-concrete interface was investigated. The sulfate corrosion environment was simulated by the sulfate full immersion corrosion test. 15 single-lap shear specimens were prepared. The load-slip curve, bond strength and interfacial fracture energy of the specimens were analyzed. Results showed that, under the sulfate attack, the bond stiffness of the specimens increased while the slip at the turning points of the load-slip curve decreased; After exposure for 300 days, the bond strength and interfacial fracture energy decreased by 17.6 and 26.0%, respectively.