Ansys Learning Forum Forums Discuss Simulation LS Dyna Pressure dependency MAT_079 Reply To: Pressure dependency MAT_079

Pedram Samadian
Ansys Employee

Hi Joerg,

When using pressure-dependent properties (e.g. A2>0 and/or B>0) in *MAT_79, you need to define the initial stresses. The soil stresses can be initialized using *INITIAL_STRESS_DEPTH or by doing a pre-analysis to obtain the *INITIAL_STRESS_SOLID cards in a dynain file. The pre-analysis would have gravity ramped up slowly from zero to its full value. 

I hope this information helps.

Pedram