Simulation of the Roll-Forming Process for the Determination of the Relevant Residual Stresses of Cold-Formed Steel Members

The uprights for pallet rack systems are usually thin-walled open cold-formed steel sections. Their behaviour under compression can be analysed experimentally, analytically or by finite element simulation. In the finite element simulation usually material non linearity, large displacements and initial geometric imperfections are introduced. But until now, the effect of the residual stresses due to the forming process, is usually non considered. With the aim of introducing these stresses in the finite element simulation, our group has started to simulate the roll-forming of open steel sections. In this paper we present our first experiences in the simulation of roll-forming of U-, C- and trapezoidal sections, some comparisons with experimental data available in the literature and the first results of the forming of a medium load upright section.