GGU-DRAWDOWN: The influence of sheet pile walls

The influence of sheet pile walls is taken into consideration via a reduction in water ingress according to HERTH/ARNDTS. The sheet pile wall is always outside of the well group.

The reduction is dependent upon the ratio of t/T, and is shown in Figure 83 (HERTH/ARNDTS). In the program, you must give the position of the drawndown groundwater level in the area of the sheet pile wall, and define the penetration depth of the wall. Input of drawndown groundwater level is necessary, as the assumption that we have here the at-rest water level, with a small distance of the well from the sheet pile wall, would lead to unrealistically large reductions.