Compressive behaviour of high strength steel cross-sections

The recent increase in the use of high strength steels in modern engineering practice necessitates a deeper understanding of their structural response. Given that high strength steel (HSS) design specifications are largely based on a limited number of test data and assumed analogies with mild strength steel, their applicability to HSS sections needs to be assessed. In this paper FE models are developed and validated against experimental data of hot-finished S460 and S690 stub columns. Parametric studies are conducted to generate a large number of structural performance data over a wide range of cross-section slendernesses and aspect ratios. On the basis of the results, the suitability of the Eurocode Class 3 limit and the effective width equations for HSS sections is assessed. Aiming to account for the element interaction effects, which are not considered in Eurocode, an effective cross-section method applicable to HSS slender sections is presented. Finally, the continuous strength method is extended to stocky S460 sections, for which overly conservative strength predictions were observed. The reliability of the proposed design methods is verified according to Annex D of EN 1990.