Current design equations given in EN 1993-1-3 for calculating the web-crippling resistance of cross-sections with one web were copied from the AISI's Specification for the design of cold-formed steel structural members, taking into account the different safety concepts: load and resistance factor design (LRFD), with resistance factors&phgr;w applied to nominal values, and limit state design, with partial factors &ggr;M applied to characteristic values as defined in EN 1990. Furthermore, the web-crippling equations of subsequent editions of the AISI specification (then designated AISI S100) were completely revised based on the web-crippling data collected and evaluated by Beshara and Schuster [5].
This paper presents the results of a calibration of a generalized web-crippling equation to be used for cross-sections with one web (i.e. C- and Z-sections). The coefficients of the generalized web-crippling equation were calibrated to comply with the safety concept described in EN 1990, taking into account EN 1990, Annex D, and a partial factor &ggr;M1 = 1.1. This paper therefore provides an introduction to as well as background information on proposed changes and amendments to EN 1993-1-3.