受轴压黏弹性层合圆柱壳的极值点蠕变失稳  

Creep buckling with limit point type for viscoelastic laminated circular cylindrical shells under axial compression

作　　者：刘一凡[1] 彭凡[1] 傅衣铭[1] 

机构地区：[1]湖南大学力学与航空航天学院,长沙410082

出　　处：《复合材料学报》2007年第6期166-172,共7页Acta Materiae Compositae Sinica

基　　金：湖南省自然科学基金(05JJ30008)

摘　　要：基于Donnell薄壳理论,采用准弹性方法,分析了含初始几何缺陷黏弹性层合圆柱壳极值点形式的延迟失稳特征。由轴向缩短量的突然增加定义失稳临界时间,对玻璃纤维/环氧树脂层合圆柱壳进行了数值计算。结果表明:圆柱壳存在临界时间趋于无穷的持久临界荷载;表征延迟失稳程度的瞬时弹性临界荷载与持久临界荷载之差值随着初始几何缺陷的增加而减小;边界条件、铺设方式对延迟失稳的影响机制可通过对应弹性层合圆柱壳的缺陷敏感性分析来考察。Based on the Donnel＇s shell theory, the creep buckling behavior, in the form of limit point, was investigated for viscoelastic laminated circular cylindrical shells under uniformly axial compression with geometrical imperfections. The quasi-elastic approach was applied to the analysis of end-shorting following elapsed time, and the critical time is determined at which the snap- through of end- shorting occurs. The numerical investigation of glass/epoxy laminated circular cylindrical shells was performed. It is shown that there exist durable critical loads which correspond to infinite critical time. The difference between transient critical load and durable critical load, which characterizes the extent of time-dependent buckling, decreases with the increase of imperfection. The mechanism of the influence on the buckling behavior for ply mode, the amplitude of imperfection and boundary conditions as well can be examined by combining the discussion on the sensitivity of imperfection for the corresponding elastic counterpart.

关 键 词：黏弹性 层合圆柱壳 极值点 延迟失稳 缺陷敏感性 

分 类 号：O344.6[理学—固体力学]