A phenomenologically based damage model for 2D and 3D-textile composites with non-crimp reinforcement

The application of textile-reinforced composites for safety-relevant structural components requires reliable predictions about their damage and failure behaviour. The potential of these materials for engineering applications has not been fully exploited so far since practical design rules disallow the occurence of any damage in the material even if the damage is not critical. In this context, the paper presents a novel damage model for textile composites with quasi-unidirectional reinforcement. A failure criterion based on the failure mode concept is adopted to describe the quasi-brittle fracture behaviour. To take into account the subsequent non-linear stiffness degradation, this approach is combined with a continuum damage mechanics model. The capability of the damage model is shown for biaxially reinforced weft-knitted glass fibre–epoxy composites.

Research highlights
► Development of a damage model with large generality for textile composites.
► Inclusion of diffuse damage (e.g. interface damage) into the design process.
► Connection of the model with a strength-based “proof of design”.
► Model verification demonstrated using a few uniaxial tests and NDT.