Hello,

when you set "Mech on" it means that it calculates the induced stresses and deformation within the model based on your defined constitutive model. it updates the calculation in each cycle to reach a stable condition or as they say the calculation converges. I guess, since you have generated pore pressure, it deteriorates the condition and makes your model instable.

regards,

Emad

Hi

Arrange Modeling earth dam:

1- construction the foundation and initial balance

2- Stage construction of the body of earth dam

3. Initial Rising water in state set flow on/mech off

4. Hydrostatic pressure of water on the crust in state set mech on/flow off

And

the amount of water bulk Modulus is very important

I believe that you have encountered this problem while generating the stresses in the model for static equilibrium. First run should be mech on/flow off and check your effective stresses. Then perform the flow analysis by setting mech off/flow on with reasonable fluid bulk modulus. Now check your PWP. This should be followed by the mech on /flow off analysis with the zero fluid modulus. you can also try with higher cohesion for the shallower zones along the slopes since it might help you in bringing the model to equilibrium.