Experimental investigation of high strength cold-formed channel sections in shear with rectangular and slotted web openings

Cold-formed steel channels with web openings in shear have been thoroughly investigated mainly with circular and square holes. However, web cut-outs are likely to be enlarged along the span length of members due to a limited web depth to provide more access for the building services in practice. The design of cold-formed sections with elongated web holes in shear was investigated and retained in the AISI S100–16 and the AS/NZS 4600:2018 using the empirical approach. This paper presents an experimental investigation of perforated channel sections with rectangular and slotted web openings in shear using a dual actuator test rig to minimise the effects of bending moments and obtain the predominantly shear capacity with an aspect ratio up to 2.0. The commercially available plain C-lipped channel sections with a depth of 200 mm and a thickness of 1.5 mm were chosen with varying sizes of central cut-outs. A new strategy for determination of the shear yield loads (Vy) together with the Vierendeel mechanism approach is presented in this study to propose a modified design for perforated channels with web openings having aspect ratios of holes up to 3.0 for the Direct Strength Method (DSM) of design of channel members in shear with elongated web openings. In addition, as required in the DSM method, the shear elastic buckling loads (Vcr) are extracted from the linear elastic buckling analyses using finite element method in this paper. •An experimental investigation of channel sections with rectangular and slotted web openings in shear is performed.•A dual actuator test rig to minimise the effects of bending moments and obtain the predominantly shear capacity is used.•Shear elastic buckling loads are extracted from the linear elastic buckling analyses using finite element method.•New strategy for determination of the shear yield loads together with the Vierendeel mechanism approach is presented.•Direct Strength Method modified design rules for perforated channels with elongated web openings in shear are proposed.