Definition of initial moisture content

hey! I got a question for modeling transient analysis when using Seep/W and Sigma/W.
I'm trying to model an embankment with a certain initial moisture content. Is there any way to define initial moisture content rather than defining only saturation state of the soil?
Since I try to analyze dissipation of water through the embankment when the fill is placed with a certain water content apart from water level or water head boundary conditions.

Thank you so much for your answers!

Answers

  • Hello! 

    You can't define the volumetric water content (moisture content) directly, but you can define an activation pore water pressure for any material (right into the material definition). You can thus activate a new lift at a target pore water pressure, the solver will then look up the volumetric water content vs matric suction curve and the soil will be activated at the desired moisture content. Of course, this can only be done for saturated/unsaturated materials. 

    For example, see the attached figures. Say I want the volumetric water content to be 33% for the new lift. Inspecting the figure, I deduce the matric suction that corresponds to this is 20 kPa, which corresponds to a pore water pressure of -20 kPa. 



    In the material definition for the new lift, I will use -20 kPa as the activation pore water pressure which will ensure the lift will start to exist at a volumetric water content of 33%.