A CONTINUUM DAMAGE MODEL FOR THICK COMPOSITE-MATERIALS SUBJECTED TO HIGH-RATE DYNAMIC LOADING

A continuum damage model (CDM) is developed to study the response of t hick laminated composite materials subjected to high-rate loading proc esses. A vector damage description is used to represent evolving modes of damage associated with certain orientations of brittle cracking of the matrix material. A simple maximum strain criterion is used for fi ber breakage with no allowance for evolution. Phenomenological damage evolution equations are postulated in terms of the current state of da mage, stress above a current threshold, and material properties contro lling evolution rates, resulting in implicitly rate-dependent response . Specific threshold and evolution functions are postulated and used t o illustrate the predictive capability of the model for homogeneous de formation fields. A comparison of results to available experimental da ta for rate-dependent behavior of graphite/epoxy laminated composites shows good agreement.