基于预警丝理念的预应力CFRP抗弯加固设计方法

PRESTRESSED CFRP BENDING REINFORCEMENT DESIGN METHOD BASED ON EARLY WARNING WIRE CONCEPT

近年来预应力CFRP板加固技术在建筑加固中得到了广泛应用,加固后构件的承载能力、抗裂度、刚度以及材料利用率得到了明显提高,但加固后构件的延性明显降低,破坏形式变成脆性破坏,破坏前无明显征兆。为解决这一问题,本文基于预警丝理论的预应力CFRP板抗弯加固设计方法,提出了将预警丝的断裂点作为构件屈服点的理论。对4根预应力CFRP板加固的钢筋混凝土梁进行了弯曲性能试验,研究表明钢筋、预警丝、承载部分碳纤维板可以协调工作,验证了基于预警丝理论的设计方法的可行性,并通过最远法验证了预警丝的断点即为加固构件的实际屈服点,成功解决了该类加固构件延性不足的问题。

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.