Crashworthiness analysis for bio-inspired hierarchical honeycomb combined with square and circular tubes

Abstract

Inspired by the microstructure of European yew, bionic hierarchical honeycomb structures combining square and circular tubes (BHSCH) is proposed in this work. Through quasi-static compression experiments and finite element analysis, the energy absorption characteristics of BHSCHs of different orders were investigated under both in-plane and out-of-plane loading. The results indicated that the in-plane energy absorption properties of BHSCH relied on the buckling and collapse between cells, with higher-order BHSCHs demonstrating better energy absorption capabilities. In out-of-plane compression, the interaction between internal units of the BHSCH structure increased with higher order, leading to significantly enhanced energy absorption and maximum crushing force. Then, a theoretical compression model was used to calculate the average crushing stress of BHSCHs of each order and analyze their energy dissipation process. Good agreements were found between the predicted and numerical results with the error of less than 10 %, proving the reliability of the proposed model. By comparing the SEA with other honeycomb structures, the BHSCH exhibited excellent mechanical and energy absorption properties. Finally, the local impact resistance of BHSCHs was investigated, exploring the energy absorption capabilities of sandwich structures with different BHSCHs under the impact of small spheres at the same velocity.