外压作用下圆柱壳的塑性初始后屈曲

Initial Postbuckling Behavior of Circular Cylindrical Shells in Plastic Range under External Pressure

本文基于塑性流动理论,利用 Hutchinson 的塑性初始后屈曲方法,研究了无缺陷圆柱壳在均匀外压作用下的弹塑性后屈曲性态.壳体材料为任意幂次强化模型.计算结果表明,对于直径厚度比 D/t<40的一类壳体,必须要考虑塑性变形,而且由此表现出来的后屈曲性态和弹性情况完全不同,它存在有压力极限值,对几何缺陷的敏感比较显著.

Based on the J_2 flow theory,an analysis is presented of the initial postbuckling behavior of circular cylindrical shells subjected to external pre- ssure by using Hutchinson's general method.The elastic-plastic material forming the shells is taken to have an arbitrary strainhardening exponent.It is shown that plastic deformation must be taken into account if the shells have a diameter-thickness ratio of less than 40.This kind of shell has a diff- erent postbuckling behavior from thin cylindrical shells and its imperfection- sensitivity is strong.