By Lynda Myer
For the first time in order to controlling water levels for the immersed Fehmarnbelt tunnel project basins, a floating gate has been moved into the harbour opening.
Considering that three basins have been constructed in front of the tunnel factory at Rødbyhavn in Denmark, the tunnel sections can be shipped out, while the effectively connection between the factory and the work harbour is also up to them. Moreover, for increasing the water level above sea level when an element is moved, the basins can be closed at both ends with gates.
With 45m wide and 21m high, the gate was built in the middle of basin B and it has eight tanks, as well as closing the entrance between the harbour and the basin, the gate has a pumping station to fill the basins.
Advancing a 10 days’ operation in September2023 the construction consortium Femern Link Contractors (FLC) filled the three large basins with water, whereas this action was done gradually so as not to damage the barriers between the basins.
With total capacity of almost 1.6 million m3 of water, each basin is nearly 11m deep.
As world’s largest precast concrete element factory, the tunnel factory has six production lines, and the casting of the first of 89 tunnel elements has commenced. Of the 89 tunnel elements, 79 are standard elements 217m long, 42m wide and 9m high. One standard element is produced from nine castings, each approximately 24m in length, meaning the first segment of the 711 segments has been cast.
According to Anders Wede: “The next milestone would be marked next year when the first finished element would be shipped out.”
Linking Rødbyhavn on Lolland in Denmark and Puttgarden on the German island of Femern, this tunnel is 18km-long.
