双面梯度多角薄壁结构的吸能特性  

Energy absorption properties of multi-corner thin-walled columns with double surface gradients

作　　者：周俊先 秦睿贤 陈秉智[2] ZHOU Jun-xian;QIN Rui-xian;CHEN Bing-zhi(College of Mechanical Engineering,Dalian Jiaotong University,Dalian 116021,China;College of Locomotive and Vehicle Engineering,Dalian Jiao tong University,Dalian 116021,China)

机构地区：[1]大连交通大学机械工程学院,辽宁大连116021 [2]大连交通大学机车车辆工程学院,辽宁大连116021

出　　处：《吉林大学学报（工学版）》2019年第5期1584-1592,共9页Journal of Jilin University:Engineering and Technology Edition

基　　金：国家自然科学基金项目(11272070)

摘　　要：梯度厚度和多折角设计是提升薄壁结构吸能效率的两种有效策略,将这两种策略联合,提出了具有双面梯度厚度的多角薄壁结构(包括方管和非凸多角管),并对其在轴向冲击下的力学行特性进行了理论分析,推导了该结构的平均撞击力理论模型。基于显示非线性有限元分析软件ANSYS/LS-DYNA对该结构进行了仿真实验研究,且仿真实验结果与理论预测值有较好的一致性。实验结果表明:增加折角数和提升厚度梯度均可有效提升管件的吸能效率。作为梯度厚度策略与多角薄壁结构的联合,具有双面梯度厚度的非凸多角管相比传统均匀厚度的方管在比吸能上提高148%~205%,充分展现了这种联合策略在提升薄壁结构耐撞性方面的高效性。Graded thickness and multi-corner designs are two efficient strategies to improve the energy dissipation of thin-walled tubes. In this study,the mechanical properties of multi-corner structures(square and nonconvex multi-corner tubes)with double surface gradients subjected to axial load were theoretically and numerically studied. An analytical formulation for the mean load of these types of novel structures was derived using the super folding element theory. The theoretical predictions agreed well with the simulation results obtained using the ANSYS/LS-DYNA software. The results show that increasing the corner number and thickness gradient can improve the energy-absorption efficiency. The combination of nonconvex multi-corner structures and double-surface gradients can lead to the increase in the specific energy absorption as high as 148% to 205% when compared to a square tube with a uniform thickness.This fully demonstrates the high efficiency of this type of combination in improving the crashworthiness of thin-walled structures.

关 键 词：薄壁结构 轴向冲击 梯度厚度 能量吸收 压溃模式 

分 类 号：O342[理学—固体力学]