Damage model for predicting shear strength of carbon/carbon composite fastener based on post-failure behavior

Fasteners made of carbon/carbon composites (C/Cs) have been developed for joining C/Cs components in high-temperature environment. A numerical damage model based on post-failure behavior was developed for simulating shear strength of 3D weave C/Cs fastener under several load angles. 3D pixel method was employed to simulate the heterogeneous damage process of constituents considering weave geometry in the macro model. Experiments were performed and the main damage as well as failure modes are also provided. It shows that the damage model can provide reasonable predictions compared to experiment data. And the damage mechanism observed in experiment can be reproduced in the numerical simulation. Furthermore, the effect of load angle on shear strength and failure modes was investigated which shows the strength of specimen decreases with increase of load angle. Numerical results showed different damage progression under several load angles which also reflected different load curve trends and post-failure behavior.