Hello, I'm trying to model an excavation in an axisymmetric 2D model.
Water pressure was defined in a particular way at the initial phase where the bottom soil layer was set to dry and the layer just above it was set to "interpolate", resulting in a diagram that is in accordance with what's in my mind:
however in the following phase where only the surface loads are activated (without changing a single thing in the model), the diagram becomes different. It was noticed there's a "jump" in the water pressure at the base of each layer as you can see in the below figure.
Can someone please give an explanation for this jump and what could be the thing leading to that change?
Note that only Phreatic is used as a pore pressure calculation type.
Thanks in advance!
Hi Mohamad,
I see that you are plotting pwater which is a combination of steady-state pore pressure, psteady, and excess pore pressure, pexcess: pwater = psteady + pexcess
It would be interesting to also plot the distribution of psteady and pexcess as they will give you more insight to your question.
Answer Verified By: Mohamad Raad
Dear Vasileios, here are Psteady and Pexcess for the initial phase:
and the same for the following phase with Pwater:
It seems that the parameter I'm looking for is Psteady in this case. Note that the two layers where excess pore pressures are generated are clayey soil and are modelled as Undrained (B) which seems the reason why excess pressures are generated due to the applied loads in that phase.
If you have any comment on the excess pore pressures plot or any tips to take into consideration please let me know, your opinion is valuable.
Thanks a lot!