Influence of the bevel and steeple triggers on crashworthiness of carbon fiber-reinforced composite channel section structure

To induce the progressive crushing of composite channel section structure (CCSS), the bevel and steeple trigger are proposed and designed. A nonlinear damage model considering both damage initiation and evolution of intra-ply and inter-ply is developed. The damage initiation and stiffness degradation processes of intra-ply are predicted by the maximum stress criterion and an exponential evolution law, respectively. The adhesion behavior between adjacent plies is modeled following the surface-based cohesive contact method, and the delamination failure behaviors of inter-ply are predicted using the traction-separation model. The effects of different configurations of bevel and steeple trigger on the energy absorption characteristics of CCSSs subjected to quasi-static axial loading are compared and analyzed. The results show the initial peak load of CCSS using the bevel and steeple trigger has a negative correlation function with the bevel angle. The steeple trigger can induce progressive crushing of the structure and significantly enhance the specific energy absorption (SEA).