A novel phase-field based cohesive zone model for modeling interfacial failure in composites

The interface plays a critical role in the mechanical properties of composites. In the present work, a novel phase-field based cohesive zone model (CZM) is proposed for the cracking simulation. The competition and interaction between the bulk and interfacial cracking are taken into consideration directly in both displacement- and phase-field. A family of modified degradation functions is utilized to describe the traction-separation law in the CZM. Finite element implementation of the present CZM was carried out with a completely staggered algorithm. Several numerical examples, including a single bar tension test, a double cantilever beam test, a three-point bending test, and a single-fiber reinforced composite test, are carried out to verify the present model by comparison with existing numerical and experimental results. The present model shows its advantage on modeling interaction between bulk and interfacial cracking.