GGU-3D-TRANSIENT: "Soil properties" menu item
After going to this menu item a system-specific dialog box opens allowing input of the transient soil properties. The steady-state properties imported from the GGU-3D-SSFLOW program can no longer be amended here.
The steady-state soil properties are supplemented by the specific storage coefficient of the fluid and the grain skeleton "Ss". The soil permeability can be altered as a function of the time using the "k = f(t) [0]" button.
The value for nw can also be entered here. The value of nw gives the volume of water relative to the total volume. It is a dimensionless variable and is a function of the pore water pressure u. Typical function curves for various soil types are shown in Figure 1:
Figure 1 Function nw = f(u)
By clicking the "nw = f(u)" button you will arrive at the following dialog box:
The table offers you the possibility of developing the specific soil curve of the soil to be processed by assigning various pore water pressures u to nw values. By clicking on the "x modelling points to edit" function box you can edit the number of modelling points. The entered values are adopted for all soil layers after an additional confirmation if the "For all" button is clicked.
Alternatively to manual input, the default values for the various soil types (gravel, sand, silt, clay) can be automatically adopted by the program by pressing the "Std" button in the above "Soil properties" dialog box.