Buckling analysis of sandwich plates with FG porous cores and graphene origami-reinforced copper face sheets using the EFG method and Carrera’s unified theory

Abstract

This paper investigates the buckling behavior of sandwich plates composed of a porous core and copper face sheets reinforced by graphene origami. To accurately capture the mechanical response, a novel numerical approach is developed by integrating the Element-Free Galerkin (EFG) method with the higher-order Layer-Wise Carrera Unified Formulation (LWCUF). The model accounts for three different porosity distributions within the core and assumes uniform origami graphene reinforcement in the face sheets, with perfect interfacial bonding. The accuracy and efficiency of the proposed method are verified against benchmark solutions from the literature, showing strong consistency. Finally, a detailed parametric analysis is performed to evaluate the effects of plate geometry, origami graphene volume fraction, porosity ratio, graphene folding degree, boundary conditions, and loading types on the critical buckling load. The findings highlight the significant role of origami graphene architecture and core porosity in enhancing the stability of sandwich structures.