Web crippling behavior of perforated cold-formed Z-sections under end-two-flange loading

Abstract

This paper aims to evaluate the web crippling behavior of the perforated cold-formed Z-sections subjected to web crippling under end-two-flange (ETF) loading. Perforated cold-formed sections are commonly used in the modern construction industry. North American Specification provides web crippling capacity for perforated C-sections under one flange load case only. Hence, a web crippling investigation for perforated Z-sections is conducted in this study. The nonlinear finite element models were developed for perforated Z-sections having centred beneath the web opening. Available experimental results from the literature are used to validate the nonlinear finite element model. Finite element models are validated for both solid web sections and perforated sections. The validated nonlinear finite element (FE) models are used to investigate the effect of web opening on the web crippling behavior of Z-sections with various web opening sizes varies from 20 to 80% of web height. The web crippling capacity of the perforated Z-sections obtained from the nonlinear finite element analysis is compared with the web crippling capacity of solid web sections. After the comparison, a suitable reduction factor equation is suggested for the perforated Z-section under end-two-flange loading.