Introducing new nested absorbers with square cross-sections and optimization of their performance using Response Surface Method under quasi-static loading

Thin-walled structures with nested cross-sections have been introduced in recent years as structures with high energy absorption capacity. In this research, a new type of energy absorbers is introduced, which is a combination of two different elements which are subjected to lateral and axial loads simultaneously. The study has been done experimentally and numerically; in the numerical part, LS-DYNA software was used for computer simulations. The outer part of the introduced absorbers has square shells with a thickness of two millimeters that absorbs energy under lateral loading. The inner part of new absorbers is a shell with a rectangular cross-section that collapses under axial compression. The obtained results showed that these structures can increase the energy absorption by 36 and 32% of the total energy absorbed through each component separately. In the experimental part, the accuracy of numerical results was checked, and good agreement was observed. In the final part of this research, using Minitab software and based on the response surface method (RSM), the most optimal absorbers in terms of specific energy and maximum force were introduced.