Shear strength reduction of aluminium lipped channel beams due to web openings

Aluminium members are recently being used as main structural elements in residential, commercial and industrial buildings. Aluminium Lipped Channel Beam (LCB) is one of the popular thin-walled sections used in different applications in construction. Web openings are incorporated in these sections to accommodate building services when they are used as beams. Even though the bending, shear and web crippling behaviours of these sections were investigated in the past, their structural behaviour with web openings have not been investigated. Hence, experimental and numerical studies were conducted in this research to investigate the shear behaviour of these aluminium LCBs with web openings. An aspect ratio of one was considered in this study. A total of 17 tests were conducted first to investigate the shear behaviour of aluminium LCBs with circular web openings using three-point loading arrangement. Finite element models were developed with appropriate loading and boundary conditions and validated using the experimental results. A detailed parametric study was then undertaken using the currently available roll-formed aluminium LCBs with different thicknesses, grades and web opening sizes. The ultimate shear capacities and the shear capacity reduction factors obtained from the tests and finite element analyses were compared with the currently available design rules. This paper presents the details and results of the experimental and numerical studies on the shear behaviour of aluminium LCBs with circular web openings and the comparison with current and recently proposed design rules.