Parametric studies and design recommendations of perforated coldformed ferritic stainless steel unlipped channels subject to web crippling under interior-one-flange and end-one-flange loadings

Abstract

A finite element and parametric study evaluations into the web crippling strength of perforated cold-formed ferritic stainless steel unlipped channels with circular web perforations under interior-one-flange (IOF) and end-one-flange (EOF) loadings are presented in this paper. The cases of web perforations located offset to the load and reaction bearing plates, are considered. In order to take into account the effect of the circular web perforations, a parametric study involving 288 finite element analyses was performed; from the results of the parametric study, strength reduction factor equations are determined. The strength reduction factor equations are first compared to equations recently proposed for lipped cold-formed stainless steel channels. It is demonstrated that the strength reduction factor equations proposed for lipped coldformed stainless steel are unreliable and unconservative for the unlipped stainless steel channels as much as 10%. New strength reduction factor equations are then proposed that can be applied to unlipped ferritic stainless steel grade.