| Natural disasters and severe environment lead to the performance degradation of existing building structures. A huge amount of money is need to repair them. Due to the advantages of fiber-reinforced polymer (FRP) material, FRP reinforced concrete in civil engineering has been widely used. While, FRP reinforced concrete structures subjected to bending often occurs FRP-concrete interface debonding, so, the FRP material performance has not been fully used, and restricts the reinforcement technology development. Therefore, the mechanical behaviors of FRP-concrete interface are the most basic and critical issues for FRP reinforced technique. The study here focuses on the different types of FRP and adhesive layer influence on mechanics performance of the FRP-to-concrete interface by the single-lap shear bond test. Intermediate crack-induced debonding in FRP-plated RC beams test and finite element analysis.In this paper, Different types of FRP and adhesive layer influence on interface ultimate bearing capacity were investigated by single-lap shear bond test. Process of FRP-concrete interface debonding, failure modes and FRP strain distribution were discussed. The results indicated that FRP stiffness has significant effect on interface ultimate bearing capacity, the effect of adhesive layer on interface ultimate bearing capacity is small. Due to the tensile strength of adhesive layer larger than concrete tensile strength, Interface failure mode usually is shear failure of concrete that near the adhesive layer, and debonding failure from the loading end to the free end. Interfacial shear stress between FRP and concrete is heterogeneous distribution.Different types of FRP and adhesive layer influence on the ultimate bearing capacity and stiffness of the FRP reinforced concrete beams were investigated by the test of intermediate crack-induced debonding in FRP-plated RC beams and finite element analysis. Process of debonding, crack distribution and FRP strain distribution was discussed by the test. Interfacial shear stress was discussed by the finite element analysis. The results indicated that FRP stiffness has significant effect on ultimate bearing capacity and stiffness, but, adhesive layer almost has no effect on ultimate bearing capacity and stiffness. Intermediate crack-induced debonding shows brittle failure. Finite element analysis was better predicted the IC debonding failure mode. Finite element analysis indicated that FRP sheet strain of the debonding area is small difference, and the interfacial shear stress distribution between cracks is jumping between tension and compression. |
