Web Crippling Behaviour of Fastened Aluminium Lipped Channel Sections

Abstract

Web crippling is a form of localized failure that thin-walled members are susceptible to in structural systems. The available literature shows limited experimental studies conducted to investigate the web crippling behaviour of aluminium members. Hence, an experimental study was carried out herein to investigate the web crippling phenomenon of fastened (flanges restrained to supports) roll-formed aluminium lipped channel sections. A total of 40 web crippling tests were carried out under two-flange load cases of End Two-Flange (ETF) and Interior Two-Flange (ITF). This paper presents the test results including the load-displacement curves, failure modes, ultimate loads and the effect of restraining flanges to the support in the web crippling behaviour. It also presents the comparison of ultimate loads from tests with the current design rules and discuss the details of the development of the new design rules. The comparison showed that the current design rules are unconservative and unreliable to predict the web crippling capacities of fastened aluminium lipped channel sections, while the new design rules can accurately predict the web crippling strengths of fastened aluminium lipped channel sections under two-flange load cases.