Thermomechanical postbuckling response and first-ply failure analysis of doubly curved panels

The thermomechanical postbuckling response of graphite/epoxy multilayered doubly curved (spherical and elliptic paraboloid) shell panels having rectangular planform is obtained within the framework of the finite element method. The nonlinear equilibrium paths are predicted using the displacement control method and the temperature-dependent material properties are used in the analysis. The structural model is based on a first-order shear deformation theory incorporating geometric nonlinearities. The first-ply failure of laminates is predicted with the Tsai-Wu failure criterion. Specific numerical results are reported that show the effects of radius-of-curvature-to-span ratio and thickness-to-span-ratio on the stability and strength characteristics of doubly curved shell panels subjected to combined thermal and mechanical loads. Moreover, numerical results are presented showing the effect of temperature dependence of material properties on limit loads and snap-through response of shallow curved panels.