Bionic-bamboo design for enhancing the crashworthiness of composite tube with groove trigger subjected to oblique load

A novel bionic bamboo-shaped tubular structure (BBSTS) was proposed to improve the energy absorption performance of composite tube under oblique crushing. A finite element model that accounts for both intralaminar and interlaminar failure initiation and damage evolution was established to investigate the crashworthiness of BBSTS subjected to oblique loading. Available experimental results verify the model. Based on the model, the complex reinforcement mechanisms of BBSTS were extensively revealed. From the predicted results, the BBSTS has better energy absorption performance compared with the original structure. It is highlighted that the bioinspired joint embedded in the fracture area of the tube exhibits a significant increment of EA (22.42%) and SEA (15.92%). Furthermore, the parametric analysis revealed the effect of the bio-inspired joint with different thicknesses and angles on the energy-absorption characteristics. This study deepened an understanding of the oblique crushing failure mechanisms of the composite tube and provides a novel structure to improve crashworthiness characteristics against oblique loading.