Energy absorption capability numerical analysis of thin-walled prismatic tubes with corner dents under axial impact

The paper presents results of a parametric study into energy absorption capability of thin-walled square section columns with redrawn dents, subjected to axial impact compressive load. Thin-walled aluminum tubes with four dents in the corners were under investigation. The varying parameters were the dent’s depth and distance of the dent to the base. The study was performed using Finite Element numerical code. Three crashworthiness indicators were examined: peak crushing force, crash load efficiency and stroke efficiency. The numerical results are shown in load-shortening diagrams, as well as diagrams and maps of crashworthiness indicators. It was found, that the main factor influencing a crushing mode and, subsequently, energy absorption capability, is a dent depth. The dent distance from the base is of less importance. Also a position of a dent, either at the bottom, or at the top base (the load application point) does not influence the crushing behavior significantly. For the deepest dents the relative increase of crash load efficiency (CLE) amounts 25% in comparison with the column without dents.