Buckling analysis of sandwich plates with FG-CNTRC layers by natural element hierarchical models

This paper is concerned with the numerical buckling analysis of sandwich plates with functionally graded CNT-reinforced composite (FG-CNTRC) layers. The core is isotropic metallic material while two face-sheets are made of polymer reinforced with CNTs. For an accurate and effective buckling analysis of advanced sandwich structures, a new numerical method is developed by making use of hierarchical models and 2-D natural element method (NEM). The hierarchical models are based on 3-D elasticity theory, in which the displacement field is interpolated as a product of 2-D in-plane unknown functions and 1-D assumed thickness monomials. The model level is adjusted by controlling the maximum orders of thickness monomials, and the 2-D in-plane functions are approximated by NEM. The numerical method is compared with the advanced plate theories, from which the numerical accuracy has been justified. Using the proposed natural element hierarchical models (NEHM), the buckling load parameters of FG-CNTRC sandwich plates are parametrically investigated. Through the parametric numerical experiments, the effects of major design parameters were profoundly investigated, and which provide the useful guideline for the buckling-resisting design of FG-CNTRC sandwich plates.