Mixed layer-wise models for multilayered plates analysis

This paper addresses the problem of the fulfillment of a number of requirem ents which are essential towards the reliable modeling of multilayered thic k prates made of anisotropic composite materials. Among them, the fulfillme nt of both the continuity of displacements and transverse shear and normals stresses at the interfaces between two consecutive layers are such necessa ry requirements. Two independent fields are assumed in the thickness direct ion for the transverse stress and displacement unknowns in each layer. Line ar, parabolic as well as the case of N-order expansion are treated. Legendr e polynomials are employed as base functions and top/bottom values of displ acement and stress components are introduced as unknown variables. Displace ment and mixed governing equations are derived by referring to the equation of virtual displacements and to a Reissner mixed variational equation, res pectively. The interface continuity conditions, referred to as C-z(0)-requi rements, 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 laminate d, thick plates and comparison with exact, elasticity results show the accu racy of the proposed models. (C) 1998 Elsevier Science Ltd. All rights rese rved.