Transition Between Progressive And Global Buckling Of Aluminium Extrusions

In order to study the transition between progressive and global buckling of axially loaded aluminium extrusions, a pilot project was carried out using the finite element code LS-DYNA. The primary variables in the numerical study were the local and global slenderness of the extruded members and the impact velocity, For impact velocities below 10 m/s the critical global slenderness at transition was increased when increasing the slenderness of the cross sectional elements. In contrast, the critical global slenderness was decreased when the impact velocity was 20 m/s. The overall response is found to be very dependent on the location of the first lobes.