Crashworthiness of bamboo-inspired circular tubes used for the energy absorber of rail vehicles

A new type of thin-walled circular tubes (CTs), which is inspired by the bamboo with highly-efficient energy absorption (EA) capability, was proposed and designed for the potential application of the energy absorber of rail vehicles in this study. And then, the axial crushing behavior and crashworthiness of the bamboo-inspired bionic tube (BT) were experimentally and numerically investigated, compared with the single CT and foam-filled tube (FT). The typical crushing responses (e.g., deformation mode, load-displacement response, energy absorption, and strain distribution) and quantitative crashworthiness indicators (EA, SEA, F-P, F-m, and CFE) of these three types of CTs were presented and discussed. Effects of impact velocity and foam relative density on the crashworthiness of tested tubes were also explored. The experimental and simulation results show that the BT specimen exhibits the best capability of load-carrying, energy absorption, and crashworthiness among three types of tubes. Compared with the CT specimen, the EA value of BT specimens increased by 93.1%, while the corresponding F-m value raised from 74.2 kN to 143.4 kN.

Automated summary

A new type of thin-walled circular tube (BT) inspired by bamboo was proposed and designed for potential application as an energy absorber in rail vehicles. Experimental and numerical investigations were conducted to study the axial crushing behavior and crashworthiness of BT, compared with single CT and foam-filled tube (FT). The results showed that BT exhibited the best load-carrying capability, energy absorption, and crashworthiness among the three types of tubes, with an increase of 93.1% in EA value and an increase from 74.2 kN to 143.4 kN in F-m value compared to CT specimens.