Mixed layer-wise models for multilayered plates analysis

This paper addresses the problem of the fulfillment of a number of requirements which are essential towards the reliable modeling of multilayered thick prates made of anisotropic composite materials. Among them, the fulfillment of both the continuity of displacements and transverse shear and normals stresses at the interfaces between two consecutive layers are such necessary requirements. Two independent fields are assumed in the thickness direction for the transverse stress and displacement unknowns in each layer. Linear, parabolic as well as the case of N-order expansion are treated. Legendre polynomials are employed as base functions and top/bottom values of displacement and stress components are introduced as unknown variables. Displacement and mixed governing equations are derived by referring to the equation of virtual displacements and to a Reissner mixed variational equation, respectively. The interface continuity conditions, referred to as C(z)(0)-requirements, have been fulfilled a priori by writing the governing equations at the multilayered level. Displacements and mixed formulations have yielded partial and complete fulfillments of such requirements, respectively. A few closed form solutions related to the bending problem of cross-ply laminated, thick plates and comparison with exact, elasticity results show the accuracy of the proposed models. (C) 1998 Elsevier Science Ltd. All rights reserved.