Structure As Retention Volume / Retention Tank; Structure Of Retention Volume; Laying Geotextile, Film And Geotextile - Graf SICKER-BLOC COMPACT 300 Anleitung

6.

Structure as retention volume / retention tank

6.1

Structure of retention volume

The preparation of the trench and the laying of the first geotextile layer is described in sections 5.1 and
5.2.
6.2

Laying geotextile, film and geotextile

Further steps follow laying the first layer of geotex-
tile.
The water-impermeable film is placed on the first
layer of geotextile, followed by another layer of
geotextile. This three-layered surround provides
protection and a water-tight shell.
GRAF and your local trading partner remain at
your service for any further information or advice
concerning waterproof film.
6.3 Structure as retention volume / retention tank
For use as a retention tank, a flow controller or a drainage throttle should be installed in a separate shaft.
GRAF and your local trading partner remain at your service for any further information or advice.
Please note:
When setting up a retention tank, it is essential to consider the groundwater level. An accumula-
tion of groundwater may cause uplift, resulting in damage to the system and its surroundings.
If you intend to install the system in groundwater, please consult with GRAF beforehand. Please
provide GRAF with the necessary information about the construction project (soil cover, ground-
water level, loading etc.) and consult on this.
Depending on the soil type, heavy rainfall may cause local rises in stratum water, particularly in
the material used to backfill the trench. When installing the retention system, check again that no
compaction of the subsoil or silting-up has taken place during the construction phase.
It may be necessary to install extra drainage. GRAF will be happy to provide advice on this.
6. Structure as retention volume / retention tank
Figure 19: 3-ply layer structure
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