Macroscopic properties of woven fabric composites by 3D numerical analysis

The mechanical properties of woven fabric composites could be predicted by two different approaches (1). The first is based on the lamination theory (see e.g. (2)) and is usually employed for approximated predictions of thermo-mechanical characteristics. The second gathers numerical refined finite element models (see e.g. (3)). In this work an approach belonging to the latter group is described. The main assumption is the periodic distribution of the reinforcements in the composite. Therefore the theoretical concepts of the homogenization theory for periodic media are exploited (see e.g. (4)). The approach is based on two levels of homogenization. The first level concerns the warp and weft yarns. They are considered as unidirectional fiber reinforced composites characterized by a fiber volume fraction equal to the packing density. The second homogenization level is performed on a representative volume of the woven composite. It is singled out and modelled by a three-dimensional finite element mesh. The assumed material periodicity is taken into account by kinematic boundary conditions. The necessary input parameters are limited to the geometry of the reinforcement and to the mechanical properties of the matrix and fibers.