I am doing the simulation of submerged water jet erosion using *MAT_FHWA_SOIL .To simulate deletion of the failed elements, I set different densities of soil, added *MAT_ADD_EROSION ,and I used the maximum shear strain as failure criteria. Does anyone have any ideas about how should I determine the value of the maximum shear strain for different densities? Is there any way to calculate?

Thank you.