Abstract

In this paper, low-velocity impact of square columns filled with density-graded foam (DGF) is investigated experimentally, numerically and analytically. The low-velocity impact experiments are carried out to study the effect of density gradient on the deformation patterns and energy absorption of the DGF-filled columns. Numerical calculations are performed to study the effects of density distribution mode, density difference, average density of DGF and wall thickness of square column on the energy absorption. According to the energy method and basic folding element theory, the instantaneous dynamic crushing force is predicted analytically. The analytical predications are in good agreement with experimental results. It is found that the DGF-filled columns have excellent energy absorption capacity and low initial peak force compared to the uniform-filled columns with the same weight.

摘要

本文通过实验、数值和分析方法研究了填充有密度梯度泡沫 (DGF) 的方柱的低速冲击。进行了低速冲击实验，研究了密度梯度对DGF填充柱的变形模式和能量吸收的影响。通过数值计算研究了密度分布方式、密度差、DGF平均密度和方柱壁厚对能量吸收的影响。根据能量法和基本折叠元理论，对瞬时动态破碎力进行解析预测。分析预测与实验结果吻合良好。