Progressive damage modeling of open-hole composite laminates under compression

Despite the recent success of modeling progressive damage of open-hole fiber reinforced composites subjected to tension (OHT), it is still a challenging task to predict the strengths and the damage progression of open-hole composite laminates under compressive loading (OHC). Herein, we propose a progressive damage model for OHC based on our early model for OHT and apply it to study the size effects of OHC. In the proposed model, continuum shell elements are used to account for both in-plane and out-of-plane deformation and delamination is modeled using cohesive elements. A smeared crack model is used to model the progressive failure of composite plies. It is found that the proposed model can predict accurately the experimental strengths and damage patterns with the assumption that the translaminar fracture toughness for blocked plies increases. The different failure mechanisms of the sublaminate scaled laminates of the stacking sequence [45/90/-45/0]ms45/90/-45/0ms and the ply-level scaled laminates of stacking sequence [45n/90n/-45n/0n]s45n/90n/-45n/0ns are found to be closely related to the in-plane shear stress of the central 0°° ply block and the initiation of interface delamination.