Numerical prediction of composite damage behavior: A modeling approach including the strain-rate-dependent material response

Prognosis of dynamic damage in fiber-reinforced plastic structures is still a challenging engineering issue. This study presents a novel approach to physically motivate the damage evolution parameters in LS-DYNA material model *MAT_058 for numerical predictions of strain-rate-dependent damage in composites. Well-characterized properties of carbon/epoxy prepreg material IM7/8552 are used as a thoroughly studied database. Models on coupon and component level are gradually investigated to reproduce the inter- and intralaminar failure mechanisms observed in open-hole-compression and crushing experiments. Stacked-shell coupon simulations agree well with experimental results. In the case of crushing, the predictive quality is excellent for double-stacked-shell models as long as the failure mode is reproduced. The study indicates the importance of a strain-rate-dependent material representation to correctly replicate the load bearing capacity in highly dynamic simulations of composites. The results of this study contribute to a more efficient design of weight-optimized composite crash absorbers and structures in general.