Simulations of Axially Loaded Straight Aluminium Profiles with Random Geometric Imperfections

Stochastic simulations of square aluminium tubes of 6060 T6 aluminium alloy subjected to axial crushing have been performed in LS-DYNA and compared to existing experiments. The main variables of the experimental study were the extrusion length, the wall thickness and the impact velocity. Three different buckling modes were observed; progressive buckling, a transition from progressive to global buckling and global buckling. In the present study it has been investigated if it is likely that geometric imperfections modelled by assumed Gaussian random fields can explain the experimentally observed behavior. Variation of the random field parameters by use of a factorial design resulted in variations in especially the buckling modes and consequently the average force.