Hygrothermal effects on the postbuckling of composite laminated cylindrical shells

The influence of hygrothermal effects on the buckling and post-buckling of composite laminated cylindrical shells subjected to combined loading of ext ernal pressure and axial compression has been investigated by using a micro -to-macro-mechanical analytical model. The material properties of the compo site are affected by the variation of temperature and moisture, and are bas ed on a micro-mechanical model of a laminate. The governing equations are b ased on the classical laminated-shell theory, including hygrothermal effect s. The non-linear prebuckling deformations and initial geometric imperfecti ons of the shell are both taken into account. A boundary layer theory of sh ell 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 p erfect and imperfect, cross-ply laminated cylindrical shells under differen t sets of environmental conditions. The results show that the hygrothermal environment has a significant effect on the interactive buckling load as we ll as post-buckling response of the shell. In contrast, it has a small effe ct on the imperfection sensitivity. (C) 2000 Elsevier Science Ltd All right s reserved.