Beam Element Material Model for Rotary-Straightened Steel W-Shapes

An inelastic material model that was previously developed by the author for standard W-Shapes was adapted for use to model the behavior and strength of rotary-straightened hot rolled W-Shape sections. Using a published residual stress model for these W-Shapes, limit load analyses were conducted using the material model in MASTAN2 and were compared with published finite element results. The material model required an adjustment to the initial yield moment conditions and residual stress ratios. Comparisons with published results indicate that these minor modifications were sufficient to provide very good modeling agreement. The previously developed material model can be used effectively to model the limit load conditions of rotary-straightened hot rolled W-Shape beams and beam-columns in steel frames. The effect of rotary-straightening W-Shapes is more significant for minor axis bending conditions and this becomes more pronounced as the floor load magnitudes increase.