Tests of channels subjected to combined bending and web crippling

Abstract

An experimental investigation of cold-formed channels subjected to combined bending and web crippling is described in this paper. A series of tests was performed on unlipped channels rolled from high strength structural steel sheets having nominal plate thickness up to 6 mm, and a maximum web slenderness value of 45. This value is considerably lower than the intended web slenderness values used in the Australian/New Zealand Standard (AS/NZS 1996) and the American Iron and Steel Institute (AISI 1996) specification for cold-formed steel structures. Therefore, the appropriateness of the combined bending and web crippling design rules for members with comparatively stocky webs is investigated in this paper. The specimens were tested at various lengths using the Interior-One-Flange loading condition specified in the AS/NZS (1996) and the AISI (1996) specification, and the test strengths are compared with the design strengths obtained from these specifications. Generally, it is shown that the specifications conservatively predicted the strengths of unlipped channels having stocky webs subjected to combined bending and web crippling.