Abstract
In order to fmd the best shape of the energy absorbing mechanisms, that are used in the vehicles as elements of passive safety during a crash, this work deals with numerical simulation of the axial, static and dynamic, collapse of thin- walled columns having circular, square, double T and C cross section and the same weight and encumbrance. Moreover the axiul crashing behaviour of circular tubes subjected to variable impact velocity is studied, to find a relationship between the impact velocity and the crash characteristic parameters. The analyses are performed by finite element method.