受轴向冲击圆柱壳非对称屈曲分析

轴向冲击荷载作用下薄壁圆柱壳屈曲变形研究一直受人们关注，探讨其动态响应的特征和机理，不仅可以丰富冲击屈曲研究内容，而且为提高结构的抗冲击能力提供理论基础。众多实验现象表明，圆柱壳在轴向冲击荷载作用下非对称屈曲时截面为规则几何形状，且不只三角形一种模式，也不是随机现象，而具有一定规律性。文章对环向截面屈曲耗能计算进行理论推导，通过分析对比屈曲耗能与折叠边数、圆柱壳半径的关系，根据最小耗能原理，证实变形规律存在，并分析得到，随半径增加圆柱壳非对称屈曲由三角形模式向多边形模式发展，最终有转变为轴对称变形模式的可能。

Analysis of Non-Axisymmetrical Buckling of Cylindrical Shells Under Axial Impact

Study on buckling deformation of thin-walled cylindrical shells under axial impact always gains a lot of attention. Thus, it is necessary to discuss the characteristics and mechanism of dynamic response of cylindrical shells. It will enrich the relevant research of impact buckling, as well as provide theoretical basis for improving the impact resistance of structures. Lots of testing results show that the section of cylindrical shell, when buckling under axial impact, is of a regular geometric shape. The deformation type of the section is not unique, such as triangle. It is not random either. But it has its own laws. Energy consumption of circumferential buckling is formulated and calculated in this paper. The relations between the number of folded edges, the radius of the cylindrical shell and the energy of buckling are also provided. In virtue of the principle of minimum energy consumption, the existence of the regulation of buckling deformation is confirmed. It shows in the analysis that as the radius of the shell increases, the non-axisymmetric buckling mode can change from the triangle shape to a polygon shape. And it is possible to change to an axisymmetric buckling shape finally.