对称正交铺层剪切圆柱壳在外压作用下的屈曲和后屈曲

给出了对称正交铺层剪切圆柱壳广义大挠度Ｄｏｎｎｅｌ方程．采用位移型摄动技术构造出计及横向剪切圆柱壳的屈曲和后屈曲渐近级数解，运用奇异摄动技术研究了圆柱壳两端部狭窄区内的边界层效应，并构造了与边界条件匹配的边界层一致有效渐近解．应用获得的当前解计算了在侧向外压作用下三层正交铺设圆柱壳的屈曲载荷并与实验值作了比较，两者十分接近．讨论了Ｂａｔｄｏｒｆ数和初始几何缺陷对圆柱壳屈曲与后屈曲性态的影响．给出的载荷－挠度关系式表明，对称正交铺层剪切圆柱壳的初始后屈曲具有弱稳定分支点．

Buckling and Postbuckling of Symmetrically Laminated Cross Ply Shear Deformable Cylindrical Shells under External Pressure

The generalized Donnell equations governing large deflection of symmetrically laminated cross ply cylindrical shells counting for transverse shear deformation are presented. A symptotic series solution is constructed by the regular perturbation technique of deflection type for buckling and postbuckling behaviors of the shells under external pressure. Effects of boudary layers designed to match with the out of plane boundary conditions are examined by singular perturbation approach within both end narrow regions of the shells. The numerical results computed from the present solution for the buckling loads for 3 layered cross ply cylindrical shells under external pressure are compared with the experiments and a close agreement is found. Furthermore, the influence of Batdorf parameters and initial imperfections on buckling and postbuckling behaviors is studied. The load deflection relations are presented with a weak stable point of bifurcation for the balanced cross ply shear flexible cylindrical shells during initial postbuckling.