Crash analysis of composite energy-absorbing cylindrical impact attenuator

Thin-walled composite structures are becoming increasingly popular over metals for crashworthy applications in the automotive industry due in part from advantages such as their higher strength to weight ratio. In this study, the analysis of the crash behavior was conducted by means of a series of quasi-static axial compression tests and LS-DYNA simulations. A set of comparative quasi-static compression tests were conducted on simple composite tubes with different lay-up orientations. Based on experimental data on load/displacement and on the comparison between results of experiments and simulations, the factors affecting energy-absorbing capacity were discussed and the mechanism of failure in composites during the crushing process was concluded. Load versus displacement diagrams confirm that the composite cylindrical attenuator shows high energy-absorbing characteristics and efficiencies. The energy-absorbing capacity is strongly affected by the ply wrap angle. Specific energy absorption increases with the increasing of angle of the fiber. Based on the analysis of these experiments and simulations, factors influencing the value of specific energy absorption are determined and design principles of composite impact attenuators are provided.