Inelastic finite element analysis of a heterogeneous medium exhibiting temperature and moisture dependent material properties

Abstract

A pseudo-three-dimensional finite element method is presented for the analysis of the microstress state within a fibre-reinforced material. The method is based on a slightly revised definition of the generalised plane strain conditions. The analysis includes both inelastic and anisotropic (transversely isotropic) material properties. The necessary material matrices for elastic isotropic, inelastic isotropic, and elastic anisotropic material behaviour are given under the conditions of generalised plane strain. A unique aspect of the analysis is that environmental dilatational strains are included in the inelastic constituent material formulations. The dependence of the material properties on temperature and/or moisture is extended into the inelastic material range. A means of incorporating these hygrothermally dependent material properties by using the Richard-Blacklock parametric modelling equations is introduced. A numerical example showing the importance of including the temperature dependence of the constitutive material properties when analysing a fibre-reinforced composite material is presented.