Continuum Models for the Analysis of Progressive Failure in Composite Laminates

The performance of continuum material models for mesolevel modeling of progressive failure in composite laminates is examined. Two different continuum models are used: a continuum damage model and a softening plasticity model. It is shown how mesh-independent results can be obtained with both models by introducing a viscosity term. The capability of the models to represent complex intraply failure behavior is assessed by means of an analysis of a notched plate, where interface elements are used to model delamination. Proper results from different modeling approaches are shown, but upon calibration a limitation of the continuum approach in the representation of matrix failure is encountered. With a second example, this limitation is emphasized further and explained as a consequence of the homogenization that is inherent in continuum models, irrespective of the applied failure criteria and material degradation laws.