Hygrothermal effects on the postbuckling of axially loaded shear deformable laminated cylindrical panels

The effect of hygrothermal conditions on the buckling and postbuckling of shear deformable laminated cylindrical panels subjected to axial compression is investigated 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 a micro-mechanical model of a laminate. The governing equations are based on Reddyʹs higher order shear deformation shell theory with von Kármán–Donnell-type of kinematic nonlinearity and including hygrothermal effects. The nonlinear prebuckling deformations and initial geometric imperfections of the panel are both taken into account. A boundary layer theory of shell buckling is extended to the case of shear deformable laminated cylindrical panels under hygrothermal environments and a singular perturbation technique is employed to determine the buckling loads and postbuckling equilibrium paths. The numerical illustrations concern the postbuckling behavior of perfect and imperfect, moderately thick and thin, cross-ply laminated cylindrical panels under different sets of environmental conditions. The results show that the hygrothermal environment has a significant effect on the buckling load as well as postbuckling response of the panel. In contrast, it has a small effect on the imperfection sensitivity of symmetric cross-ply laminated cylindrical thin panels.