Effect of different parameters on the performance of FRP anchors in combination with EBR-FRP strengthening systems: A review

The use of fiber-reinforced polymer (FRP) composites using externally bonded reinforcement (EBR) installation technique is an alternative to conventional retrofitting techniques for retrofitting and strengthening deficient structures to improve their seismic performance. In spite of this widespread application, premature failure caused by FRP sheets debonding from the concrete surface is one of the greatest challenges faced when FRP composites are used for structural strengthening. FRP anchors (FRP spike anchors) proved their ability to suppress or postpone FRP debonding and can provide safe means to transfer and guide the load from one member to another in FRP strengthening of reinforced concrete (RC) structures. This study aims to provide an overview of the effect of different parameters on the performance of FRP anchors in RC structures strengthened with FRP composites. This study also tries to review the various design models in order to determine the capacity of FRP anchors according to a failure mode approach or a bond-slip approach. Finally, despite wide research on the behavior of FRP anchors, there are some issues and research gaps like the effect of cyclic loading, different environmental situations, temperature, creep, and fatigue on the behavior of FRP anchors as well as a comprehensive and unified model to predict FRP anchor capacity in different conditions that still need to be investigated and clarified that are mentioned in this paper