Nonlinear local bending of FGM sandwich plates

Abstract

This paper investigates the nonlinear local bending of a sandwich plate consisting of two composite laminated face sheets and a graded core subjected to a lateral patch load. It is assumed that the material composition of the graded layer varies symmetrically along the thickness direction according to a power law distribution. The present analysis is based on the first order shear deformation plate theory and von Karman nonlinear kinematics, with the interaction between the loaded face sheet and the graded core being modeled as an elastic plate resting on a Vlasov-type elastic foundation. A perturbation technique and Galerkin method are used to determine the nonlinear local bending response. Numerical results show that compared with conventional sandwich plates with a homogeneous soft core, the use of a functionally graded core can effectively reduce both the local deformation and interfacial shear stresses. A parametric study is performed to show the influences of the volume fraction index, Young's modulus ratio, thickness of the graded core, boundary condition, and load position.