An efficient modelling of inelastic composites with misaligned short fibres

•Efficient elastoplastic models of behaviour for short fibre reinforced composites.•Modelling of a compressible plastic flow for the matrix, all kinds of hardening laws.•Easy modelling of random or misaligned orientations of fibres. This paper deals with the modelling of the behaviour of short-fibre reinforced composites. The composite is seen as an assembly of a matrix medium and of several fibre media. Each fibre medium, characterised by its own orientation of fibres and volume fraction, is considered as a one-dimensional elastic medium. The matrix material has an elastoplastic behaviour. All types of hardening laws can be considered, thanks to a valuable adaptivity of the modelling. The use of the Drucker–Prager criterion for plasticity and non-associative plasticity rules allow to deal with compressible plastic flow. Moreover, all kind of orientation of fibres, in particular random orientations and imperfect alignments, can be modelled in a simple way. The influence of the fibres’ orientation on the mechanical response of a polymer matrix composite subjected to tensile/compression tests is analysed in detail. Finally, simulated behaviours of composites are compared to experimental data found in the literature.