ABSTRACT
In this paper, non-linear finite element models were developed for the web crippling of cold-formed lean duplex stainless steel (CFLDSS) square and rectangular hollow sections under the concentrated interior bearing loads at elevated temperatures (up to 950 °C). The interior bearing loads cover the loading conditions of Interior-One-Flange (IOF) and Interior-Two-Flange (ITF). The web crippling design rules in the current international specifications were examined. It was found that the predictions by the North American Specification were generally unconservative and not reliable, while the European Code provided reliable but very conservative predictions. New design method, the Direct Strength Method, was proposed for the web crippling strength of CFLDSS tubular sections at elevated temperatures under the loading conditions of IOF and ITF. The assessments indicate that the new method provides better strength predictions than the codified design rules. The new predictions are overall conservative and reliable.
