Thermomechanical postbuckling of shear deformable laminated cylindrical shells with local geometric imperfections

The effect of local geometric imperfections on the buckling and postbuckling of shear deformable laminated cylindrical shells subjected to combined axial compression and uniform temperature loading is investigated. Two cases of compressive postbuckling of initially heated shells and of thermal postbuckling of initially compressed shells are considered. The governing equations are based on Reddy’s higher order shear deformation shell theory with a von K arm an–Donnell-type of kinematic nonlinearity and including thermal effects. The material properties are assumed to be independent of the temperature. The nonlinear prebuckling deformations and initial geometric imperfections of the shell are both taken into account. A boundary layer theory of shell buckling is extended to the case of shear deformable cross-ply laminated cylindrical shells and a singular perturbation technique is employed to determine the buckling loads and postbuckling equilibrium paths. The numerical illustrations concern the compressive or thermal postbuckling behavior of moderately thick, cross-ply laminated cylindrical shells with local or modal geometric imperfections. The results show that, for the same value of amplitude, the local geometric imperfection has a small effect on the buckling load as well as postubuckling response of the shell than a modal imperfection does.