FRP plates bonded on concrete with different FRP anchor configurations

Fiber-reinforced polymer (FRP) composites are recognized for their high tensile strength, strength-toweight ratio, corrosion resistance, easy installation, and versatility. A large number of studies conducted to date (e.g. [1-3]) have shown the significant increases in the load capacities of concrete members through FRP strengthening. However, due to high interfacial shear and normal stresses at the FRP-toconcrete interface, debonding failure modes such as plate end debonding, concrete cover separation, and intermediate crack-induced debonding were frequently reported in previous studies [1-5]. Such debonding failure results in the premature failure of the FRP plate strengthening system before it develops its full strength. The use of anchorage has emerged as one of the most promising techniques for delaying or preventing interfacial debonding failure in concrete members retrofitted with externally bonded FRP laminates [6]. It was shown in previous studies that the use of FRP spike anchors results in increases in both the bond strength at the FRP-concrete interface and axial strain in the FRP plate, allowing a more efficient use of the FRP material [5]. A review of the literature has shown that the effect of anchor configuration on the behavior of FRP plates with multiple anchors has not been sufficiently studied. This study was aimed at addressing this gap.