Since the Arge Tunnel ElbX consortium, comprising Porr GmbH and Wayss & Freytag Ingenieurbau, began tunnelling in February, the TBM has progressed approximately 2.8km beneath the Elbe River.
Porr says the work is taking place under challenging geological and technical conditions. Beneath the Elbe River, the TBM is now traversing the particularly challenging Lauenburg clay. Additionally, compressed air work at pressures of up to 4.8 bar is required under the shipping channel. This limits operating time at the cutterhead to just 50 minutes per shift – requiring significant personnel resources for continuous monitoring and tool changes.
Work on the two shafts is also progressing. In Schleswig-Holstein, the second basement level is under construction, while in Lower Saxony, work is beginning on the fifth basement level. The specialist foundation engineering work for the excavation pit of the target shaft was completed two months ago; the civil engineering team is now constructing the shaft structure.
TenneT Germany’s grid expansion project will transport electricity over 700km from Brunsbüttel in Schleswig-Holstein, northern Germany, to Großgartach in Baden-Württemberg, southern Germany.
The 5.2km-long tunnel, which has a 4m inner diameter, will house six 525kV direct current cables, connecting the SuedLink underground cables on both sides of the Elbe. An integrated rail system will enable efficient maintenance and repair work in the long term.
