I am modelling a system subjected to a thermal shock, where in there are both vertical cracks (mode I ) and also infacial cracks (cracks that primarily fail by delaminaton-mode II)

 For vertical cracks, Iam able to get reasonable answers for mode I crack propagation in ABAQUS using a critical crack opening displacement criterion. However when it comes to interfacial crack, I dont know how to propagate it becz all the criterion in the debond subroutines in abaqus assume a mode I kind of crack opening.

Is my assumption wrong ? Can anyone help me out in this?

Thanks