Anisotropic damage induced by complex fibre orientations in short-fibre reinforced composites
Résumé
In this study, the behaviour of short-fibre reinforced composites is modelled in an original way that does not require complex homogenisation procedures. The composite is seen as the assembly of a matrix medium (metal or polymer) and several one-dimensional linear elastic fibre media. The matrix has elastoplastic (possibly compressible) and damageable behaviour. Damage characteristics are directly correlated to the reinforcement characteristics and can therefore be fully anisotropic. The matrix behaviour is solved using a semi-coupled elastoplastic-damage scheme, in the framework of non-associative plasticity. The fibre axial stress is computed for each fibre media using a modified shear-lag model that takes into account the progressive degradation of the fibres/matrix interface due to matrix damage. Finally, the macroscopic behaviour of the composite is solved using an additive decomposition of the state potential. The model is validated thanks to comparisons with experimental data extracted from the literature.