A continuum damage model for fiber reinforced laminates based on ply failure mechanisms

A ply-level damage model for simulation of stiffness degradation due to progression of damage in fiber reinforced laminates is presented. The proposed damage model is based on damage mechanisms observed at the ply level and hypotheses regarding their effect on material stiffness. Focusing on matrix dominated failure modes, the damage behavior is split into two contributions, damage evolution and damage effect. The prior describes the progression of damage as a function of load, while the latter predicts the effect of this damage by a fourth order tensor relation as function of the current failure mode and stress state. The model relies on six material parameters, whose identification by standard tests is addressed. By combining the damage model with classical lamination theory, the behavior of laminates under plane stress loading is predicted. The capabilities of the proposed damage model are assessed based on comparison to experimental data from the literature.