OPTIMUM DESIGN OF COMPRESSED COLUMNS OF CONSTANT WELDED SQUARE BOX CROSS SECTION CONSIDERING THE EFFECT OF RESIDUAL WELDING STRESSES.

The calculation of overall buckling stress is made by means of buckling curves developed by the European Convention of Constructional Steelwork. In these curves the effect of initial imperfection and that of residual welding stresses is considered. On the basis of Okerblom's method a simple formula is given for the calculation of residual compressive stresses in the rods of square box cross sections. For the calculation of the effective width of plate elements and that of local buckling stress, a simplified D. Faulkner's formula is used, which also takes into account the effect of residual welding stresses.