Prediction of damage progression in notched tensile specimens: comparison between two intralaminar damage models

In this work, two intralaminar damage models with different underlying assumptions are utilized to predict the damage response of notched composite laminates. One is a sub-laminate based continuum damage model, CODAM2, implemented in LSDYNA, and the other is a ply-based damage model, ABQ_DLR_UD, that uses the Ladevèze damage model as its basis and is implemented as a user-material model (VUMAT) in Abaqus/Explicit. Aside from the base-formulations, different variations of the models including local and nonlocal integration (smearing) schemes are also considered. These models are employed to predict the damage response of Over-Height Compact Tension (OCT) and scaled center-notched specimens made out of IM7/8552 CFRP laminates with quasi-isotropic layup. For each geometry and loading scenario, sensitivity of the predictions with respect to various damage parameters including peak stress and fracture energy as well as assumptions made on the shape of the strain-softening curve are investigated. The results shed light on the effect of various assumptions in these two models on predicting damage progression in notched composite specimens.