有限长圆柱壳受径向冲击的塑性动力屈曲分析

讨论两端固定的圆柱薄壳在均布外部冲击下的塑性动力屈曲。依据实验现象对位移场作出假设，用扰动法求得屈曲的扰动控制方程组，降阶后用标准的龙格库塔法进行数值求解。其中物理关系采用Ｌｅｖｙ－Ｍｉｓｅｓ流动理论，材料为刚线性强化模型。计算结果同Ｆｌｏｒｅｎｃｅ等的Ｂｅｓｓｅｌ函数解作了比较，对边界对屈曲的影响作了讨论。本文的结果对潜艇抗水下爆炸的研究有重要意义。

Dynamic Plastic Buckling of Finite Cylindrical ShellsDue to External Impulsive Loading

The dynamic plastic buckling of finite length cylindrical shells fixed at two ends due to externalimpulsive loading is studied in this paper.Hypothetical displacement field of the shells based on theexperiments is taken to derive the buckling governing equations by the perturbation method. then theequation is solved by a generalized fourth order Runge-Kutta method after lowering the order.TheLevy-Mises flow law of incremental plasticity is used and the material is assumed as line strain harden-ing. The results of this paper is compared with the Bassel function solution of Florence's and the edgeeffects are discussed.it is found that the dynamic plastic buckling of cylindrical shells subjected to a u-niform impluse is enhanced because of the fixed ends, the critical mode number of shells increases withdimensionless axial length (L/a) and decreases with thickness of shell.The results presented are im-portant to the study of withstanding explosion of submarine structure.