Structural response of FRP-to-concrete joints under cyclic actions: Fracture mechanics and fatigue analysis

Fiber-Reinforced Polymers (FRPs) are getting more and more common in structural strengthening of Reinforced Concrete (RC) members, also in seismic areas. However, the current knowledge about their mechanical behaviour and interaction with the existing materials is based on the big deal of research carried out in the last twenty years with almost exclusive reference to the case of monotonic loads. Therefore, in the last years both experimental tests and theoretical studies have been presented in the scientific literature for scrutinising the response under cyclic actions of FRP strips glued to concrete. Based on a model recently proposed by the Authors, this paper aims at unveiling the relationship between fracture-mechanics-related parameters and the resulting fatigue response of FRP-to-concrete adhesive joints. Moreover, it shows the influence of physical quantities and mechanical properties on the resulting fatigue curves.