Numerical Study on Aluminium Lipped Channel Sections Subjected to Web Crippling Under Two-Flange Load Cases

Abstract

The use of thin-walled aluminium alloy members in construction has significantly increased during the recent years due to its appealing characteristics. However, they are highly susceptible to web crippling failure due to its lower elastic modulus. In addition to the experimental study conducted by the authors, a numerical study was carried out to further investigate the web crippling phenomenon of unfastened aluminium lipped channel sections under two flange load cases. Subsequently, a detailed parametric study was conducted to thoroughly investigate the web crippling bearing capacities of a wide range of aluminium lipped channel sections including different material properties, sectional geometric parameters and bearing lengths. The extensive FE web crippling capacity data were then used to assess the accuracy of the web crippling design rules provided by the Australian design guidelines for aluminium structures. It was found that the current equations are unconservative and unreliable to predict the web crippling capacity of aluminium lipped channel sections under two flange load cases. Thus, suitable modifications were proposed to the current web crippling design equation. It is shown that the modified design rules closely predicted the web crippling strengths for aluminium lipped channel sections.