Partial Hybrid Elements for Analysis of Composite Laminates

Abstract

A composite structure is usually made of hundreds of orthotropic laminae with different fibre orientations. The finite element analysis for composite structures is more difficult than that for structures made of isotropic materials. Due to the complex nature of composites, there are many different approaches to model them. In general, the finite elements for analysis of composites can be classified into three classes: 3-D solid elements, laminated elements, and multilayer elements [4.1]. They are formulated using two classes of composite structure models[4.2–4.3] as follows:

• 1. 3-D continuum models[4.4–4.6], in which each of the individual layers of a composite structure is treated as a three-dimensional continuum. Due to simplicity and efficiency, a special 3-D model, layer-wise models [4.13–4.16], is often used, in which displacement models are based on piecewise approximations of the response quantities in the thickness direction.

• 2. Equivalent single-layer plate/shell models[4.7–4.12], in which deformable models are based on global through-the-thickness displacement, strain and stress approximations;