Finite element model for the extension of the direct strength method to hot-rolled profile cross-sections

in Proceedings of the 12th Nordic Steel Construction Conference (2012, September 05)

Abstract: In the present research, a geometrically and materially nonlinear analysis using the FE method has been conducted to evaluate the resistance of axially compressed hot-rolled H profile cross ... [more ▼]

Abstract: In the present research, a geometrically and materially nonlinear analysis using the FE method has been conducted to evaluate the resistance of axially compressed hot-rolled H profile cross-sections. The FE model was firstly duly verified against experimental data and then used to carry a parametric analysis. The goal of the analysis is to propose a new Direct Strength Method (DSM) strength curve intended for calculating the resistance of non-compact and slender hot-rolled H profile cross-sections. [less ▲]

Extension of the Direct strength method to hot-rolled profiles cross-sections

in 6th European Conference on Steel and Composite Structures : Eurosteel 2011, Budapest 30 October - 2 September 2011 (2011, September)

Current metallic structural design codes use the concept of section classification for determining the section capacity of hot-rolled profiles. In this system, there exists a discontinuity between the ... [more ▼]

Current metallic structural design codes use the concept of section classification for determining the section capacity of hot-rolled profiles. In this system, there exists a discontinuity between the classes 2 and 3, while for the class 4, the effective width method (EWM) must be used to account for local buckling phenomenon. In order to overcome the complicate and time consuming EWM for evaluating the strength, the alternative Direct Strength Method (DSM) approach, developed only for cold-formed thin-walled members, has gained importance over the last few years. The DSM is premised on the assumption that the strength can be predicted from the yield strength to the elastic critical load ratio in conjunction with a strength curve. The DSM has been advanced for calculating the strength of compression members over the past decades and in this paper, the extension of DSM to hot-rolled profiles cross-sections is investigated. Firstly, the methods for calculating the cross-section resistance such as EWM, DSM, and the recent Continuous Strength Method (CSM) are reviewed; a short comparison is made and their domains of applicability are commented. Secondly, a numerical model carried out in the frame of this research is described. The model was built in ABAQUS and verified against test results of the “Semi-comp: Plastic member capacity of semi-compact steel sections - a more economic design” project, which was carried out earlier with the objective of improving the utilization of plasticity in rolled and welded sections with medium cross-section slenderness. On the basis of these premises, the final goal of the project is detailed: to derive a new formulation that would cover the whole field of section slenderness (present class 1 to class 4), which can be seen as an extension of the so-called DSM approach. [less ▲]