Design of CFRP-strengthened aluminium alloy tubular sections subjected to web crippling

Abstract

Web crippling of aluminium alloy tubular structural members may occur due to the highly concentrated loadings. A nonlinear finite element analysis was performed based on a series of laboratory tests on carbon fibre–reinforced polymer (CFRP) strengthened aluminium alloy tubular structural members subjected to web crippling.resistance (capacity) factor The end-twσuo-flange (ETF), interior-two-flange (ITF), end-one-flange (EOF) and interior-one-flange (IOF) loading conditions specified in the North American and Australian/New Zealand specifications for cold-formed steel structures were used in this study. Nonlinear finite element models were developed and verified with test results. The material properties of aluminium alloy, adhesive and carbon fibre reinforcement polymer were taken into consideration. The traction separation law of the cohesive zone model was used to simulate the debonding between the CFRP plate and aluminium alloy tubes in the nonlinear analysis process. Geometric and material nonlinearities were also included in the finite element analysis. The finite element results explained the behaviour of the CFRP-strengthened aluminium alloy specimens subjected to web crippling. The finite element results demonstrated that the ultimate load-carrying capacity (web crippling strength), web crippling failure modes, and web-deformation curves agreed well with the tests. The verified finite element models were then used for an extensive parametric study of different tubular dimensions. This paper presents numerical data from the finite element analysis for a total of 151 simulations. It was found that the verified finite element models provided an effective and time-efficient means of predicting the web crippling strengths of CFRP-strengthened aluminium alloy members. Design equations are proposed to predict the web crippling strengths of CFRP-strengthened aluminium alloy tubular sections against web crippling loading.