DSM DESIGN OF LIPPED CHANNEL COLUMNS UNDERGOING LOCAL/DISTORTIONAL/GLOBAL MODE INTERACTION

This work aims at contributing towards extending the domain of application of the available DSM, by making it capable of estimating the ultimate strength of cold-formed steel lipped channel columns affected by local/distortional/global interaction. The current DSM expressions, as well as those applicable to interactive buckling design, are first introduced and an extensive numerical (shell finite element) study involving fixed columns is reported − the column geometries are selected in order to have nearly coincident local, distortional and global buckling loads. The numerical ultimate strength values obtained are then used to assess the accuracy of the DSM expressions. As a preliminary recommendation, the current DSM expressions are adequate to estimate the collapse load of lipped channel columns affected by local/distortional/global interaction.