Abstract: In recent years, the prestressed CFRP plate reinforcement technology has been widely used in building reinforcement. The bearing capacity, crack resistance, stiffness and material utilization rate of the strengthened members have been significantly improved. However, the ductility of the members after reinforcement is significantly reduced, and the failure mode becomes brittle failure, and there is no obvious sign before the damage. In order to solve this problem, based on the prestressed CFRP plate bending reinforcement design method and the early warning wire theory, the theory of using the breaking point of the warning wire as the yield point of the component is proposed. In this paper, the bending performance tests of four prestressed CFRP plates reinforced concrete beams were carried out. The research results showed that the steel bars, the warning wires and the carbon fiber plates can work in coordination, which verified the feasibility of the design method based on the early warning wire theory. The far method verified that the breakpoint of the warning wire is the actual yield point of the reinforcement member. The design method successfully solved the problem of insufficient ductility of the reinforcement member.

Key words: warning wire, yield point, prestressed CFRP plate, bending reinforcement, ductility