Mechanical Properties Of CFRP-steel Interface And Reinforcement Experimental Study At Elevated Temperature

Retrofit steel structure with CFRP is an important part in the field of modern steel structure reinforcement,and has gradually become a common form of steel structure reinforcement engineering.Compared with the traditional steel structure strengthening form,CFRP strengthening technology has many advantages,such as no stress concentration,convenient to construct and maintenance.At present,scholars have conducted a lot of researches on the field of reinforce steel structure with CFRP,but there are few researches on the performance of CFRP-steel composite structures under high temperature,and many problems have not been uniformly explained,therefore,multidimensional experimental investigation is important to lay a foundation for it.This paper studies the performance of CFRP-steel composite structure under high temperature by using the specimen form of CFRP laminate/steel double lap joints(bond with four structural adhesives).The specific contents are as follows:1)Using 25? as a control,conduct quasi-static tensile test with CFRP laminate/steel double lap joints under high temperature section(55?/70?/90?),three kinds of adhesives were used in the test(Lica?Sika30?HJY).accord with the test,we will acquire the modes of specimens under different temperature levels,ultimate strength,load displacement curve,strain distribution on the surface of CFRP plate,and then calculates the interface shear stress distribution and the bond-slip curve.2)Using 25? as a control,conduct quasi-static tensile test with CFRP laminate/notched steel(the length of the notch is 3cm)plate test specimen under high temperature section(55?/70?/90?),three kinds of adhesives were used in the test(WSB?Sika30?HJY).accord with the test,we will acquire the modes of specimens under different temperature levels,ultimate strength,load-displacement curve,displacement-strain curve.Based on the observation of two kinds of experimental phenomena and the analysis of collected data,we will describe the bond performance of CFRP-steel interface under high temperature conditions,evaluate the reinforcement performance of CFRP-steel structure under high temperature environment,put forward the influence rule of high temperature on CFRP-steel composite structure,which can provide reference for engineering.