Experiments and proposed model for residual stresses in hot-rolled wide flange shapes

This paper proposes a new residual stress model for hot-rolled wide flange steel cross sections. For this purpose, a dataset of 85 residual stress measurements is first assembled. The dataset is comprised of prior measurements available in the literature that are complemented by additional ones as part of the present study. A constrained optimization problem is then formulated by assuming parabolic residual stress distributions for both the flanges and the web of hot-rolled wide flange cross sections. The parameters of the developed residual stress model are inferred from the results of the optimization method and from rigorous statistical analyses. The results demonstrate that the cross-sectional area and the depth-to-width ratio strongly influence the residual stress distributions in the flanges and the web of a hot-rolled wide flange profile. The results suggest that there is no evidence that the yield strength of the material influences the developed residual stresses within a cross section. Contrary to available residual stress models in the literature that may be applicable for a limited range of cross-sectional geometries, the proposed model reduces the mean error between all available measurements and predictions by 60%-70%. The variance of the error is also reduced by a factor of two to four across all known cross-sectional properties.