A Local Model for Bending of Weak Core Sandwich Plates

Abstract

A bending theory is developed for a three-layer sandwich plate consisting of a weak core and two unequal face sheets. In the model, the core and face sheets are modeled as separate homogeneous plates with an assumed stress field, which satisfies equilibrium point-by-point. Local bending, including shear deformation, of the face sheets is taken into account. Although the usual assumption of negligible in-plane stresses in conjunction with a weak core is adopted, the effects of interlaminar core shear and normal stresses, along with transverse core flexibility, are included in the analysis. The corresponding displacement field consists of a combination of assumed and weighted displacements. Field equations are developed from Reissner’s energy theorem, and appropriate continuity conditions between the core and face sheets are enforced. The theory is applied to a rectangular plate subjected to a distributed load and to an end-loaded cantilever plate under cylindrical bending.