On the fracturing behaviors of FRP-strengthened concrete structures influencing of interfacial material capacities

The applications of Fiber Reinforced Polymer (FRP) sheets as tension reinforcement have been widely used in repair and upgrading of concrete structures. The significance of the bond is due to its critical role on transferring the stress from the existing concrete structures to externally bonded FRP sheets and keeping integrity and durability of the composite performance of FRP-concrete system. So how to improve the interfacial load transferring performances and ductility and how to improve the strength efficiency of FRP materials should raise more concerning. In this paper, a numerical simulation code named Realistic Failure Process Analysis was used to estimate failure mode of FRP-reinforced concrete beam with different bond between FRP and concrete, which has different mechanics parameters. The numerical test predictions are compared with experimental results, the numerical tests show that properties of the interfacial adhesive layer and concrete are considered to significantly influence the failure modes and crack distribution. The interactions between the interfacial bond strength and tensile strength of concrete are discussed through a parametric study; the effects of these properties on the interfacial debonding types and concrete crack distribution are clearly studied.