On dive: Removal of the diaphragm wall in the Spreekanal
Not only is progress being made underground at the underground station Museumsinsel, but progress is also becoming increasingly visible in the water of the Spreekanal: the Fangedamm in the Spreekanal has been dismantled. A total of around 2,500m³ of sand was removed and around 1300m² of sheet piles were pulled out of the earth. Both were then transported away by barge and working vessel via the Spreekanal.
This was followed by the next step: the dismantling of the diaphragm wall, which was erected in 2012 under the protection of the coffer dam. To this end, the area between the diaphragm wall and the structure wall was first flooded so that the steel reinforcements that had previously supported the diaphragm wall could be removed.
Now the diaphragm wall is cut into individual pieces weighing up to 30 tons with the help of wire saws. As the wall is being removed down to the riverbed depth of the Spree Canal, part of the work is being carried out under water: First, holes were drilled in the diaphragm wall. Divers now have to thread the ropes of the saw through these holes. In this way, the diaphragm wall is gradually dismantled into individual parts and removed until all traces of the underground station construction in the Spreekanal have been removed.