A higher-order sandwich plate theory accounting for 3-D stresses

In this paper we extend a layerwise higher-order shear-deformation theory t o model a sandwich plate impacting with an elastic foundation at a low velo city. A new concept of sublaminates is introduced, and the new sandwich pla te theory satisfies the continuity conditions of interlaminar shear and nor mal stresses, accommodates the normal and shear stresses on the bonding sur faces, and accounts for non-uniform distributions of transverse shear stres ses in each layer. Moreover, the use of sublaminates enables the modeling o f shear warpings that change with the spatial location, vibration frequency , and loading and boundary conditions. A finite-element model based on this sandwich plate theory is derived for performing direct transient analyses to predict the initiation and location of critical matrix crack and the thr eshold of impact damage. Moreover, analytical shear warping functions, shea r coupling functions, and normal strain functions due to in-plane stretchin g, bending, transverse shearing, and surface loading are presented. (C) 200 1 Elsevier Science Ltd. All rights reserved.