Abstract

The continuous effort to achieve more efficiency of steel structures results to decrease their weight. Generally, it is accepted that the weight decreasing of steel structures could be achieved mainly by their geometrical and material optimization, using the thin- walled cross-sections and the higher strength steels. The results of numerical analysis of middle and higher strength structural steels using in compression members are presented in the paper. The homogeneous I cross-sections of the members with web slenderness β_w = 40, 48, 60, 80, 120; member length L = 3,0; 4,0; 5,0; 6,0 m and structural steels S235, S275, S355, S420 and S460 were assumed. The full theoretical plastic load N_pl, local post-critical load N_ul and global buckling load N_uy and N_uz for all considered members by the European standards EN 1993-1-1 and EN 1993-1-5 for the design of steel structures were calculated. It is known that these standards have been transformed into national standards of all CEN countries which are generally used from 2010. The effective applying of the higher strength steels on the compressed members taking in consideration their shaping and material optimization is presented in this paper. The obtained numerical results are compared and analysed by choosing technical parameters.

Keywords: Compressed steel members; Homogeneous crosssections; Yield stress; Post-critical behaviour; Local and global buckling load