Postbuckling analysis is presented for a simply supported, shear deformable laminated plate with piezoelectric actuators subjected to the combined action of mechanical, electric and thermal loads. The temperature field considered is assumed to be a uniform distribution over the plate surface and through the plate thickness and the electric field is assumed to be the transverse component Ez only. The material properties are assumed to be independent of the temperature and the electric field. The governing equations of a laminated plate are based on Reddy's higher order shear deformation plate theory that includes thermo-piezoelectric effects. The initial geometric imperfection of the plate is taken into account. Two cases of the in-plane boundary conditions are considered. A perturbation technique is employed to determine buckling loads and postbuckling equilibrium paths. The numerical illustrations concern the postbuckling behavior of perfect and imperfect, symmetric cross-ply and antisymmetric angle-ply laminated plates with fully covered or embedded piezoelectric actuators under different sets of thermal and electric loading conditions. The effects played by temperature rise, applied voltage, the character of in-plane boundary conditions, transverse shear deformation, plate aspect ratio, fiber orientation and stacking sequence as well as initial geometric imperfections are studied.

A post-buckling analysis is presented for a stiffened laminated cylindrical shell of finite length subject to combined loading of external pressure and axial compression. The formulations are based on a boundary layer theory of shell buckling which includes the effects of the nonlinear pre-buckling deformation, the nonlinear large deflection in the post-buckling range and the initial geometrical imperfection of the shell. The "smeared stiffener" approach is adopted for the stiffeners. The analysis uses a singular perturbation technique to determine the interactive buckling loads and the post-buckling equilibrium paths. Numerical examples cover the performances of perfect and imperfect, stiffened and unstiffened cross-ply laminated cylindrical shells. Typical results are presented in dimensionless graphical form.

Thermal postbuckling analysis is presented for a simply supported, shear deformable laminated plate subjected to a uniform temperature rise and resting on an elastic foundation. The material properties of the com posite are assumed to be functions of temperature. The formulations are based on Reddy's higher order shear deformation plate theory, and including the plate-foundation interaction and thermal effects. The initial geometric imperfection of the plate is taken into account. A perturbation technique and an iterative numerical procedure are employed to determine the buckling temperature and thermal postbuckling load-deflection curves. A program is developed for the purpose and many examples are solved numerically. The numerical illustrations concern the thermal postbuckling behavior of antisymmetric angle-ply and symmetric cross-ply laminated plates under different sets of thermoelastic properties and without an elastic foundation or resting on two-parameter elastic foundations from which results for Winkler elastic foundations are obtained as a limiting case. The effects played by transverse shear deformation, plate aspect ratio, total number of plies, fiber orientation, foundation stiffness as well as initial geometric imperfections are studied.

The influence of hygrothermal effects on the buckling and post-buckling of composite laminated cylindrical shells subjected to combined loading of external pressure and axial compression has been investigated by using a micro-to-macro-mechanical analytical model. The material properties of the composite are affected by the variation of temperature and moisture, and are based on amicro-mechanical model of a laminate. The governing equations are based on the classical laminated-shell theory, including hygrothermal effects. The non-linear 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 laminated cylindrical shells under hygrothermal environments and a singular perturbation technique is employed to determine the interactive buckling loads and post-buckling equilibrium paths. The numerical illustrations concern the post-buckling behaviour of perfect and imperfect, cross-ply laminated cylindrical shells under different sets of environmental conditions. The results show that the hygrothermal environment has a significant effect on the interactive buckling load as well as post-buckling response of the shell. In contrast, it has a small effect on the imperfection sensitivity.

A compressive postbuckling analysis is presented for a laminated cylindrical shell with piezoelectric actuators subjected to the combined action of mechanical, electric and thermal loads. The temperature field considered is assumed to be a uniform distribution over the shell surface and through the shell thickness, and the electric field is assumed to be the transverse component Ez only. The material properties are assumed to be independent of the temperature and the electric field. The governing equations are based on the classical shell theory with von K