Failure behaviour of triaxial braided composites

In the presented work, we propose a framework for predicting the non-linear mechanical response of triaxial braided composites using meso-scale finite element unit cells. Based on a reduced unit cell concept which exploits symmetries to minimise computational expense, a compacted and interpenetration-free yarn geometry is created within a three stage simulation process. Out-of-plane periodic boundary conditions allow an implicit consideration of the compaction of multiple braid plies in different nesting configurations, which further enables us to render high global fibre volume fractions (55-60%) using experimentally determined intra-yarn fibre volume fractions. Numerical predictions are compared to experimental data in terms of stress-strain curves.