Nonlinear buckling and postbuckling responses of sandwich cylindrical panels with layered corrugated FG-GRC core resting on elastic foundation

Abstract

An analytical framework is developed to investigate the nonlinear buckling and postbuckling behavior of sandwich cylindrical panels composed of functionally graded graphene-reinforced composite (FG-GRC) face sheets and a layered corrugated FG-GRC core. The panels are subjected to axial compression and external pressure while resting on Pasternak elastic foundations in a thermal environment. A modified homogenization model is proposed for the layered FG-GRC corrugated core, extending previous formulations of single-layer configurations to include thermal effects. Two types of corrugation geometries, trapezoidal and round, are considered, and various graphene distribution patterns are applied to optimize the stiffness of the FG-GRC core. The governing equations are derived using Donnell-type shell theory in conjunction with von Karman geometric nonlinearity, and the Ritz energy method is employed to obtain the critical buckling load expression and postbuckling equilibrium paths. Parametric studies are conducted to assess the influence of core geometry, graphene distribution, elastic foundation stiffness, thermal effects, and panel dimensions. The results highlight the substantial improvements in structural stability offered by layered corrugated cores and provide valuable insights for the design of advanced FG-GRC sandwich structures under combined mechanical and thermal loads.