Hello all, 

I'm currently working on a project to investigate the effect of hydrostatic pressure on cutting of granite using a PDC cutter. I've reached the point where my results at ambient have been validated (with experimental results) but the application of a pressure load is not leading to an increase in the cutting force in the simulation. 
My hypothesis was that since the D-P model increases the strength of the material it would also result in a higher cutting force. Am I wrong with my understanding here or am I missing something in the model that needs to be accounted for. 
Currently the material model has the following: Density, Elastic, D-P plasticity, D-P hardening, Damage and Damage evolution criteria. Any inputs would be greatly appreciated and I'm happy to provide any additional information. 

Abaqus ​​​​​​​