Composite FEM Analysis for Layered Systems

A composite characterization and accompanying finite element analysis for layered systems is presented. The model is developed for plane strain and axisymmetric (horizontal layers) configurations with stiff, relatively thin isotropic layers of reinforcement sandwiched between layers of relatively flexible isotropic matrix material. Potential applications include elastomeric bearings and reinforced earth structures. The composite theory, in addition to capturing the overall response characteristics of the layered system, approximately models the important edge effects which occur at boundaries and the stress concentrations at layer interfaces. The primary dependent variables for the composite theory have been selected such that the highest derivatives appearing in the strain energy function are first order, thus requiring only C0 continuity of the finite element approximations. As a result, the accompanying finite analysis is simple and computationally efficient. Numerical examples are presented to verify the theory, compare it to previous results, and to illustrate potential applications of the analysis.