Nonlinear thermo-mechanical buckling responses of FG-GPLRC catenary caps and circular plates

Abstract

An analytical framework is developed to investigate the nonlinear thermal and mechanical buckling behavior of functionally graded graphene platelet-reinforced composite (FG-GPLRC) catenary caps resting on nonlinear elastic foundations. The formulation is based on the first-order shear deformation theory (FSDT) coupled with von Kármán-type geometric nonlinearity. The cap geometry follows a catenary profile, from which spherical caps and circular plates emerge as special cases when the curvature radius is constant or tends to infinity, respectively. The graphene platelets are embedded within a copper matrix and graded through the thickness using various distribution patterns. By employing the Galerkin method, explicit expressions for thermal critical loads and postbuckling paths under both thermal and external pressure are derived. A comprehensive parametric study is performed to examine the influences of cap geometry, foundation parameters, and GPL distribution on the stability characteristics, offering insights into the design of curved FG-GPLRC structures under combined loading conditions.