Analytical prediction of large mass impact damage in composite laminates

Analytical models are suggested for prediction of impact damage initiation and growth during quasi-static response caused by large mass impactors. Comparisons with experiments are presented for different layups, geometries and boundary conditions. The critical load for delamination growth is found almost insensitive to geometry and boundary conditions. The critical energy for delamination growth is separated in bending, shear and indentation contributions. Further growth depends on the number of delaminations developing, and is in thin laminates limited by the early occurrence of penetration. Observed delamination sizes are compared with a suggested upper bound and predictions based on the observed number of delaminations. (C) 2001 Elsevier Science Ltd. All rights reserved.