Numerical modelling of cold-formed steel single C-section portal frames

This paper presents a comprehensive investigation of the numerical modelling of cold-formed steel single C-section portal frames using shell elements. The model accounts for the semi-rigid behaviour of connections using mesh-independent point-based fasteners at the location of physical bolts. The behaviour of deformable fasteners is ascribed though the use of connector sections. Nonlinear analysis is carried out to obtain the load-displacement response leading to the prediction of frame strength. The predicted strengths of frames are compared with experimental results. The main cause of the observed flexural-torsional buckling behaviour of frames is highlighted and the importance of using an accurate fastener model is emphasized.