For PressureDependMultiYield material, there are 2 ways to achieve undrained loading conditions:
1. Use PressureDependMultiYield and set the permeability to very low (e.g. 1E-09 m/s). You need to use u-p elements (e.g., quadUP) for such purpose.
2. Use FluidSolidPorousMaterial and PressureDependMultiYield together. In this case, you may just use regular elements (e.g., quad).
The permeability for PressureIndependMultiYield material is usually very low (e.g. 1E-09 m/s).
Hope this helps though I'm not sure I fully understand your question.
-Jinchi
PressureIndependMultiYield
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