Enhanced bi-directional crushing performance of thin-walled tubes filled with laterally reinforced honeycomb cores

A novel laterally reinforced honeycomb core is proposed to enhance the axial and lateral crushing performance of thin-walled tubes by preserving the classical in-plane hexagonal topology and embedding transverse stiffeners. Quasi-static crushing tests demonstrate that, compared with hollow tubes, aluminum tubes filled with the proposed core fabricated via fused deposition modeling (FDM) exhibit a 220.4 % increase in energy absorption (EA) and a 77.2 % increase in specific energy absorption (SEA) in the lateral direction. Under axial crushing, EA increases by 107.9 %, while SEA improves by 14.7 %. A numerical model was developed, incorporating ductile damage in the aluminum tube and interlayer cracking in the proposed FDM core, and it accurately predicted the lateral crushing response of the proposed core-filled aluminum tube with <5.4 % prediction error in mean crushing force. Simulation results further reveal that, despite accounting for only 6.9 % of the total structural mass, the plastic dissipation of the stiffeners contributes 34.9 % of the total structural energy absorption. Moreover, parametric simulations demonstrate that aluminum tubes filled with a laterally reinforced honeycomb core incorporating six stiffeners achieve a 194.4 % higher lateral SEA than the hollow tube.