STABILITY RESPONSE OF FLEXIBLY CONNECTED COLD-FORMED STEEL SPACE FRAMES

Results for the elastic (bifurcation) stability analysis of cubic spac e frames composed of bisymmetrical cold-formed steel sections are pres ented. The influences of flexible connections and partial warping rigi dity are considered. Calculation of the critical load is based on a fi nite element eigenvalue algorithm which combines a secant iteration, d eterminant search routine with a 'shifted' inverse iteration strategy. A parametric study on the effect of connection and warping rigidity f or the frames subjected to gravity and lateral twist loading is presen ted. Effects of column orientation and member stiffness on frame stabi lity are discussed.