Stochastic modelling of continuous glass-fibre reinforced plastics - considering material uncertainty in microscale simulations

This paper presents a probabilistic micromechanics-based approach to simulate the influence of scatter sources in composite materials as an alternative to deterministic approaches. Focus is given to the effect of microscopic and macroscopic voids, material inhomogeneity induced by manufacturing processes and stochastic fibre patterns on the mechanical properties of continuous glass-fibre reinforced polymer components. Various periodic unit cells of neat resin and embedded fibre clusters are generated with random distributions of the abovementioned scatter sources. Subsequently, the models are mechanically loaded under transverse tension as an exemplary case and the resulting responses are correlated with the stochastic inputs. Larger pore sizes and high porosity strongly reduce the strength of the neat resin and the transverse strength of unidirectional composites. However, the strength of the fibre/resin interface is predicted to have the highest influence on the mechanical properties. The present approach is suggested as a computational efficient but reliable alternative to geometrical representations of imperfection in composite materials