Finite element simulation of slender thin-walled box columns by implementing real initial conditions

This paper deals with the numerical simulation of tests on slender thin-walled box columns, susceptible to combined instability: to global Euler buckling and to local buckling of steel plates. Eight full-scale tests were carried out with different global slenderness of welded and cold-formed columns subjected to centric and eccentric compression. Initial column geometry and residual stresses were measured and carefully implemented in numerical models. The results of FEA simulations show good agreement with the test results. On verified numerical model the influence of different initial imperfections was studied and various equivalent geometric imperfections were tested for the considered column configurations.