ABAQUS

Hey… I modeling crack propagation, for a hyperelastic material, under cyclic loading conditions. Has anyone been able to model this before, or know if its possible as I’m experiencing many problems, such as its not cracking. I’m able to simulate a crack with a ramp load and preform simulations with a higher force, but when loading and unloading it seems as no fatigue is taking place! It may be I’m not selecting an option. Any help would be much appreciated.