Adaptation of the direct strength method to stainless steel cold-formed sections

Abstract

Cold-formed thin-walled steel members are very efficient for structural purposes; they produce structures that save a large amount of material, therefore being economical. These sorts of members suffer from a series of instability phenomena, among those local buckling, distortional buckling and global buckling. Design procedures need to take into account all those instabilities to provide realistic and efficient guidance. The direct strength method is auseful tool to design cold-formed members with many advantages over the effective width method which is currently the main design method in many specifications worldwide. Its approach is more realistic and calculations are simpler and faster though it requires computational support. Unrelatedly, stainless steel has shown to be very beneficial for several structural applications. Current stainless steel members design guidance emulatesthe one of carbon steel leading to huge simplifications and so poor results. The goal of this paper is to study the application of the direct strength method to stainless steel members and propose an adaptation of the method. Specifically, local buckling determination is studied in austenitic and ferritic stainless steel columns.