By lyndamyer
The determined date for commencing tunneling process on Germany’s SuedLink ElbX, which will carry power cables under the River Elbe, is later this year.
As conductor of the €250m contract for transmission system operator TenneT TSO, Porr said that diaphragm walls are progressing so work on the underwater construction pit is on schedule to start next month.
Providing possibility of transforming renewable power from wind farms in northern Germany to the south of the country, The SuedLink will be in the alignment that includes a 5.2km tunnel crossing under the Elbe between Schleswig-Holstein and Lower Saxony.
The location of starting the works for Porr is in Wewelsfleth, Schleswig-Holstein, where the tunnel is due to run almost 20m below the Elbe to the shaft at Wischhafen, Lower Saxony. As the two shafts are at groundwater level, the construction pits have to be made waterproof with diaphragm walls of up to 50m deep prior to excavation.
Following that the 25m-deep construction pit is slated to be dug underwater, drained and secured with steel girders and the TBM, designed for the variable geology of clay, peat, sand, gravel and boulders, will be assembled. The tunnel will be completed using segmental lining.
Additionally, in order to providing the access, infrastructure required for subsequent use will be constructed in Schleswig-Holstein and Lower Saxony during the tunnel boring phase.
Over the winter, severe weather has also presented challenges for construction.
According to Robert Krause, project manager at Porr Germany: “High and sudden wind loads endanger crane operation. The rain-soaked ground makes soil removal, transport and construction site logistics more difficult.”
