Two methods were used to construct seal walls in order to minimise water leaching from the enclosed area.
Membrane wall installation
In this method, a heavy steel beam is rammed into the ground using a vibratory hammer. As the piles are extracted, a sealing wall mixture made of bentonite, water, rock flour and cement is injected under pressure into the resulting cavities. This process occurs almost seamlessly, which creates a jointless wall. At the Langes Feld site, we were able to create membrane walls on an industrial scale to depths of up to 33m.
Diaphragm wall installation
These diaphragm walls were installed in two separate cycles using the two-phase technique. In the first phase, the soil is excavated while a pure bentonite slurry is used to stabilise the diaphragm walls.
In the second phase, the support fluid is replaced with the actual diaphragm wall material. The drained bentonite is used to create the separation layer.