GGU-DRAWDOWN: "Sump pumping" menu item (for rectangular excavation only)
Sump pumping after Davidenkoff can be analysed using this menu item if you have chosen a rect-angular excavation at the beginning.
The analysis is performed compliant with equation 167 after Herth/Arndts. The variable H is defined differently here compared to conventional definitions. For a clear definition, the variable has been renamed as “Ha” (see the figure below).
From a technical perspective, the following boundary conditions must also be adhered to:
Unconfined groundwater table.
Content of settleable materials < 0.3 mg/l (to prevent uncontrolled soil removal).
In case of dry excavations: permeable drainage layer between the excavation base and the blinding course. Filter stabilities must be tested and demonstrated.
In case of large water volumes: horizontal drain pipes, which may be installed beneath the excavation base.
If you would like to subsequently display the analysis results in a legend, activate the "Display values in legend" check box in the dialog box shown above. With the check box activated you can use the "Copy to clipboard" function to copy the data to the Windows clipboard and then paste it into your report, for example.