Experimental Study And Numerical Simulation Of CFRP Reinforced Compression Square Steel Pipe

The research and application of CFRP reinforced concrete structures in the industry is very mature and widely used in engineering construction,but there are few studies on CFRP reinforced steel structures,especially the reinforced steel tubular column members,and there is no relevant theoretical data.There is also no complete steel structure reinforcement design specification including CFRP cloth in China.On the basis of summarizing the existing researches of this group,this paper supplements the test of six sets of compressed square steel tubular column scale members including one set of unreinforced and five sets of CFRP reinforcement members.In this paper,the experimental phenomena,stress and strain,and ultimate load are analyzed.Subsequently,the formula for calculating the ultimate stability bearing capacity of the compression-compressed section method is constructed reference the <Strengthening metallic structures using externally bonded fibre-reinforced polymers> guidebook compiled by the British Construction Industry Research and Information Association.And the calculation results is compared with the test results.Using ABAQUS large-scale finite element calculation software to build a model to simulate the experimental components of this paper,and verify the validity of the model.The supplementary test results of the ultimate stability bearing capacity of the member are compared with the model calculation results,which proves that the ultimate stability bearing capacity of the member obtained by the ABAQUS finite element model established by the method is more accurate.The finite element model and the orthogonal experiment design are used to simulate more CFRP-reinforced with different slenderness ratio and calculate their ultimate stability bearing capacity.The influence of slenderness ratio,CFRP layer number and eccentricity on ultimate stability bearing capacity of CFRP strengthened steel tubular column members is analyzed.Finally,the data is fitted to obtain the calculation formula of the ultimate stability bearing capacity of CFRP-reinforced steel tubular columns with correction factor of the ultimate stability bearing capacity calculation formula.This subject is supported by national standard “Design code for strengthening steel structure” and the research findings of this paper will provide theoretical and experimental bases for writing this standard.