Numerical prediction of strength of notched UD laminates by analyzing the propagation of intra- and inter-laminar damage

To predict the strength of notched unidirectional (UD) fiber reinforced laminates, computational modeling method is shown as well as its verification. Both intra-laminar damage such as fiber breaking, matrix cracking and fiber-matrix interface debonding and inter-laminar damage such as delamination occur and propagate up to the final breaking. In the proposed numerical method, the occurrence of the intra-laminar damage is judged by Hoffman's failure criterion and its propagating behavior is theoretically formulated by anisotropic damage mechanics. The delamination is numerically treated by introducing inter-laminar element (IE) in the finite element analysis. Applying the proposed method to CFRP laminates with a hole under tensile load, the damage mode in each lamina and the notched strength have been predicted. By comparison with the experimental results, the validity and the reliability of our simulation have been recognized.