Micromechanics modeling of composite materials subjected to multiaxial progressive continuum damage

The High-Fidelity Generalized Method of Cells (HFGMC) micromechanics model is extended to include constituent scale progressive damage via a proposed damage model. The damage model assumes that all material nonlinearity is due to damage in the form of reduced stiffness, and it utilizes six scalar damage variables (three for tension, three for compression) to track the damage. Damage strains are introduced that account for interaction among the strain components and that also allow the development of the damage evolution equations based on the constituent material uniaxial stress-strain response. Local final failure criteria are also proposed based on mode-specific strain energy release rates and total dissipated strain energy. The micromechanics-damage model is applied to a unidirectional E-glass/epoxy composite.