COLLAPSE BEHAVIOR AND ENERGY ABSORPTION OF CORRUGATED TAPERED TUBES

Abstract

Thin-walled structures have been widely used in energy absorption and safety applications such as automotive vehicles and locomotives, due to their lightweight, progressive folding modes, and reduced manufacturing costs. This thesis studies the collapse behavior and energy absorption performance of corrugated tapered tubes (CTTs) as potential efficient thin-walled structures under axial and oblique loading conditions. The study was conducted using experimentally validated numerical finite element model. The proposed CTT design is impacted under seven different loading angles with a striker mass of 275 kg and 15 m/s velocity. The material assigned to the proposed design structure is AA6060 aluminum alloy. The effect of loading angles and geometric parameters on various performance indicators, such as the initial peak force (IPF), mean crushing force (MF), energy absorption (EA) and specific energy absorption (SEA) were studied. The results showed that the amplitude of corrugation is the most influential factor on the force-displacement characteristics of CTTs. Also, IPF was found to be reduced when corrugation is adopted (a maximum reduction of 93.38%), especially for longer corrugation’s amplitudes and wavelengths, while EA and SEA were found to be reduced slightly. Furthermore, it was found that increasing the impact angles from 0° to 40° leads to a reduction of 54% in EA and SEA. In addition, global Euler buckling was found to develop at higher impact angles for CTTs of 80° tapered angles. Finally, it was found that CTTs of 85° tapered angle and 1-mm thickness can achieve higher SEA relative to their tapered conventional counterparts under all loading conditions (40% and 9.5% increase under axial and 40° impacts, respectively).