泡沫填充的薄壁圆柱壳体轴向压碎的分析模型

由于填充轻型泡沫的薄壁钢管有良好的耗能能力而被广泛地应用于工程中。当结构轴心受压时,钢管与泡沫芯之间的作用对吸收能量起到关键作用。已有理论研究的大部分对象为完全填充的钢管。本文提出了一个理论模型,用于分析部分填充的钢管的轴向对称压碎性能。采用改进的模型分析壳体,并考虑了泡沫芯的作用。由能量平衡原理得到极限压力的平均值。建议公式得到的结果与先前文献中的结果吻合。参数分析用于研究泡沫芯稳定时期的压力值(σf),以及填充的比例和壳体的径厚比对结构轴向受压性能的影响。为薄壁结构的吸能性能方面的设计提供指导。

An Analytical Model for Axial Crushing of a Thin-Walled Cylindrical Shell with a Hollow Foam Core

A thin-walled tube filled with light-weighted foam has wide engineering applications because of its excellent energy absorption capacity.When the structure is axially crushed,the interaction between the tube and foam core plays an important role in its energy absorption performance.Previous theoretical studies so far have largely been concerned with fully in-filled tubes.In this paper,a theoretical model is proposed to predict the axi-symmetric crushing behaviour of such structures but with a partial infill.Using a modified model for shell and considering the volume reduction for the foam core,the mean crushing force is predicted by the energy balance.The proposed formula agrees well with previous results reported in literature.A parametric study is carried out to examine the contribution of foam core plateau stress(σf) ,amount of filling and shell’s radius-to-thickness ratio(R/h) on the axial crushing behaviour of the structure.This study can give valuable design guidelines in using thin-walled structures as an energy absorber.