A bionic method for the crashworthiness design of thin-walled structures inspired by bamboo

Abstract

In natural environment, many biological structures are tubular and exhibit excellent mechanical properties that can reduce self-weight effectively and transport more water and nutrients, such as bamboo. In this paper, the structure of bamboo was introduced to increase the axial and lateral energy absorption of thin-walled tubes by using bionic design method. Energy absorption ability of bamboo was tested by drop-weight experiments. The results showed that the energy absorption was excellent due to the gradient distribution of vascular bundles, nodes and density. These advantages of the bamboo make it possible to design of bionic structure which composed of 1 bionic node and 3 bionic inner tubes with 18, 9 and 4 bionic elements in each inner tube. Numerical examples of bionic structures under axial/lateral impacts were solved with nonlinear finite element method (FEM). The results indicated that the bionic design enhances the specific energy absorption (SEA) of tubes. Thus, the bionic structure is exactly excellent energy absorption under lateral/axial impact and can be used in the future.