An analytical model to predict stress fields around broken fibres and their effect on the longitudinal failure of hybrid composites

This paper presents an analytical model to predict the stress redistribution around broken fibres in hybrid polymer composites. The model is used under the framework of a progressive failure approach to study the load redistribution around breaks in hybrid composites. The outcomes of the model are validated by comparing it with a spring element model. Moreover, the approach is further used to study the tensile behaviour of different hybrid composites. The results obtained show that the load redistribution around breaks depends on the stiffness ratio between both fibres as well as the matrix behaviour considered and the hybrid volume fraction. Furthermore, the different material parameters have a large effect on the tensile behaviour, with an increase of ductility achieved if the failure process of the two fibres is gradual.