Dynamic process of ring systems as energy absorber subjected to lateral impact loading

Abstract

This paper presents both experimental and numerical investigations on the dynamic behaviour of one-dimensional ring systems subjected to lateral impact loading. This work investigates the energy absorbing and stress-wave propagation characteristics of such ring systems for engineering design. The experiments on energy absorption were performed by making use of a modified split Hopkinson pressure bar test system together with a high-speed digital camera device. Three-dimensional numerical simulations were performed correspondingly to simulate the dynamic process. The numerical results are shown in a reasonable agreement with the experimental results. The features including energy absorption, wave elimination and stress-wave variations after collapse were investigated in detail. The energy absorption ratio is primarily affected by the thickness and the number of rings, while the impact velocity and the inner radius play a minor role. After the stress wave propagates through one-dimensional ring systems, the amplitude of the stress wave may be greatly eliminated. However, once the densification happens, it is observed that the amplitude of the transmitted stress wave may increase greatly, which should be noticed in safety considerations.