By rosebell
Following commencing the tunneling process in February by the Arge Tunnel ElbX consortium, comprising Porr GmbH and Wayss & Freytag Ingenieurbau, the TBM has advanced around 2.8km beneath the Elbe River and excavation of the ElbX Tunnel for Germany’s SuedLink grid expansion project has reached the halfway mark.
Considering the challenging geological and technical conditions, currently the TBM is traversing the particularly challenging Lauenburg clay under the Elbe River as Porr says.
Also, due to need of compressed air work at pressures of up to 4.8 bar 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.
While advancing the work on the two shafts, in Schleswig-Holstein, the second basement level is under construction, whereas 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.
Transporting electricity over 700km from Brunsbüttel in Schleswig-Holstein, northern Germany, to Großgartach in Baden-Württemberg, southern Germany, TenneT Germany’s grid expansion is a huge project.
Linking the SuedLink underground cables on both sides of the Elbe, the 5.2km-long tunnel with a 4m inner diameter is going to house six 525kV direct current cables. An integrated rail system will enable efficient maintenance and repair work in the long term.
