FE 05.0210/2021/NGB - Further model calculations for the design of sedimentation spaces
Discharges of road drainage are planned in accordance with the RAS Ew 2005 (Guidelines for the construction of roads, part: drainage), REwS (Guidelines for the drainage of roads) and RiStWag (Guidelines for structural measures on roads in water protection areas) and must also be evaluated with regard to the material pollution of the water bodies in the case of new construction measures. In addition to treatment in retention soil filters, treatment in sedimentation basins (settling basins according to RAS-Ew/REwS or RiStWag plant) is used.
Well-functioning sedimentation tanks must be cleaned of sediments on a regular basis, as sediment discharge can take place during heavy rainfall events if the sediment height is too high. A sludge or sediment collection space that only fills up over time has not yet been defined. As a result, there are no specifications for the design of the sludge collection chamber and the sludge or sediment height at which a settling tank must be cleaned.
Within the framework of the research project 05.0191/2015/NGB "Design of sedimentation areas", two categories of tailings plants have already been investigated on the basis of model calculations. For other frequently built basin categories and for other characteristics of the basin types investigated so far, corresponding findings are still lacking. Therefore, these basin categories will also be modeled.
The aim of this research project is to carry out investigations (three-dimensional numerical modelling) for other typical tailings ponds in order to derive reliable recommendations as to the sediment height and the cleaning intervals at which the basins must be cleared. When designing and evaluating the modelling, the regulations of road drainage and the practical possibilities of the road maintenance service must be taken into account. The pool facilities are selected in consultation with the client and the group of supervisors; By inspecting and evaluating existing planning documents, the contractor determines the basic data for the model structure and for the input parameters.