Postbuckling of shear deformable cross-ply laminated cylindrical shells under combined external pressure and axial compression

A postbuckling analysis is presented for a shear deformable cross-ply lamin ated cylindrical shell of finite length subjected to combined loading of ex ternal pressure and axial compression. The governing equations are based on Reddy's higher order shear deformation shell theory with von Karman-Donnel l type of kinematic nonlinearity. The nonlinear prebuckling deformations an d initial geometric imperfections of the shell are both taken into account. A boundary layer theory of shell buckling, which includes the effects of n onlinear prebuckling deformations, large deflections in the postbuckling ra nge, and initial geometric imperfections of the shell, is extended to the c ase of shear deformable laminated cylindrical shells under combined loading cases. A singular perturbation technique is employed to determine interact ive buckling loads and postbuckling equilibrium paths. The numerical illust rations concern the postbuckling response of perfect and imperfect, unstiff ened or stiffened, moderately thick, antisymmetric and symmetric cross-ply laminated cylindrical shells for different values of load-proportional para meters. (C) 2001 Elsevier Science Ltd. All rights reserved.