Inverse Identification of Micromechanics and Fracture Mechanics-Based Damage Evolution Law of Brittle Composites

This paper demonstrates identification of parameters associated with damage evolution laws defined in a micromechanics and fracture mechanics-based constitutive model for damage-tolerant brittle composites. A recently developed inverse analysis methodology, called Self-Optimizing Inverse Method (Self-OPTIM), has been extended to the identification of the physics-based damage evolution laws, which has not been achievable. The Self-OPTIM can automatically self-correct the Damage Parameter Set (DPS) based on global in-situ measurements. The material response is obtained from force-driven and displacement-driven nonlinear finite element (FE) simulations. The adopted micromechanics and fracture mechanics-based damage constitutive model can reasonably simulate nucleation and subsequent growth of microcracks within brittle composite materials. It has been implemented within the Self-OPTIM software framework. Numerically simulated synthetic data from an impact tension test are utilized to show successful performance of the proposed damage identification method.