Modelling and probabilistic study of the residual stress of cold-formed hollow steel sections

Cold-formed Hollow Steel Sections (HSS) are widely used in the construction industry. The distribution of residual stress in non-stress-relieved cold-formed HSS is complex due to the highly non-uniform variation around the cross-section and through the plate thickness. Modeling residual stress in frame analysis is therefore a difficult task. This paper presents a practical method for approximating the effects of different components of residual stress on the behavior of cold-formed HSS by modifying the steel stress-strain curve. The method proposes a convenient means of including residual stress in beam element-based nonlinear frame analysis. A probabilistic study is then carried out to study the effect of the uncertainty in residual stress on frame strength.