Micromechanical modelling coupled to a reliability approach for damage evolution prediction in composite materials

This work is based on Mori and Tanaka's work combined with statistical tensile strength theories for the computation of the effective properties of composites. In order to describe the entire behaviour of composite materials, statistical local damage criteria are introduced representing interface, fibres and matrix. The damage accumulation process is described by the microcrack density, which increases according to probabilistic considerations. In fact, the Weibull distribution applied at the microscale level arises as a key model for the strength of composite materials. In addition, the representation of the failure processes of each constituent gives a more accurate prediction of composite material behaviour. Specific results are given for composites reinforced by aligned or randomly oriented fibres and for particulate material called Twintex(R), developed by Vetrotex(R).