Water above the Terrain
The water above the terrain is a special type of surcharge, which models the water table which does not cross into the soil body. It is typical for water reservoirs which are separated from the soil body by impermeable membranes.
In this case, the water table acts perpendicular to the terrain as a surcharge with magnitude of hydrostatic pressure.
The "Water above the terrain" surcharge type
The water table is represented by one point with coordinates [x, z]. The program considers the water in an area bordered by the terrain or task edge and intersecting defined point.
If there is a different liquid than water in the tank, the program allows us to input the unit weight of this liquid. In this case, the program calculates the hydrostatic pressure of liquid with inputted unit weight. When using the EN1997 verification methodology, the partial factor on water γw is used.
It is not correct to consider the standard influence of water in the area where the water table is already defined as a surcharge. In this case, the program shows a warning in the analysis and output document. The warning is also shown if two or more "Water above the terrain" surcharges act on the same terrain parts.
Warning about water table overlap