Column curves for elliptical hollow section members

A thermo-mechanical finite element analysis model is developed to predict residual stress patterns in hot-rolled sections. The model is first verified against experimental measurements for residual stresses reported for I-sections reported in the literature. The method is then used to predict residual stresses in elliptical hollow sections. A sensitivity analysis is then conducted to assess the influence of various input parameters of the model on the predicted residual stress patterns. The effects of cross-section geometric parameters on the residual stress distribution are then investigated.A series of column curves is generated providing the compressive capacity of a column as a function of slenderness. The column curves are generated based on a) elasto-plastic geometrically nonlinear analyses, b) including the effect of residual stresses as predicted from thermo-mechanical analyses and c) incorporating initial geometric out-of straightness according to the fundamental buckling mode as predicted from an elastic buckling eigen value analysis. Generated column curves are then compared to those in current design codes. A best fit for the numeric results obtained is conducted to cast them in a format similar to that in the current codes.

Research highlights
► Investigated a technique to predict residual stresses in hot-rolled sections.
► Predicted residual stresses in hot-rolled elliptical hollow sections (EHS).
► Developed column curves for EHS including residual stresses and initial imperfection.