Experimental study of roll-formed aluminium lipped channel beams in shear

Use of aluminium sections as primary load bearing members has recently expanded considerably in the building industry. Aluminium as a new constructional material has several advantages in building structures including corrosion resistance, durability, high strength-to-weight ratio, reduced cost of transportation and ease of erection and fabrication. The popularity of aluminium structures has attracted attention regarding the efficiency and design of many sections, and roll-formed lipped channel beam (LCB) is one of these commonly used sections. However, aluminium LCBs are prone to shear buckling failures due to its increased web slenderness and low elastic modulus compared to steel. Hence an experimental study was conducted to investigate the shear behaviour of LCBs and to verify the current design rules to accurately predict the shear strengths. Shear tests have been conducted using ten different generally available roll-formed aluminium LCBs. The test sections were loaded at mid-span at the shear centre until failure. The results obtained from the tests were then compared with the predictions using the current shear design rules in the Australian/New Zealand standards and Eurocodes for both aluminium structures and cold-formed steel structures as their shear behaviour are quite similar. This paper presents the details and results of this experimental study and comparison with shear design rules based on current design rules.