In the large production halls, which really ramped up in 2022, work is now being done at high pressure in hall B to produce the first of a total of 79 tunnel elements.
In the first months, FLC has been busy tying rebar, and Jens Ole Kaslund, technical director of the developer Femern A/S, now reports that the floor, which consists of a base plate of rebar, is finished in the first segment.
– The factory functions almost like an assembly line, and the floor has now been pushed on to the next part of the process into our scaffolding setup, where the floor must have walls on it. Once the walls have been put on, the segment can be pushed on to casting, explains Jens Ole Kaslund.
Pulled by sleds
A standard tunnel element weighs 73,500 tonnes, is 217 meters long and consists of nine segments, each 24 meters long and 42 meters wide.
When the floor of the segment needs to be moved from one work station to the next in the production hall, it is done with the help of special sleds called “skidding beams”, which pull the reinforcement construction with the help of very powerful and synchronized hydraulic pistons. They ensure a very precise maneuver so that the segment is not damaged.
Impressive sight
– It is impressive when you stand next to it and see how big just one segment is and think that nine segments have to be made just to produce one tunnel element. 711 segments must be produced before we are completely finished, says Jens Ole Kaslund.
In addition, 10 special elements with a basement floor must also be produced for use with equipment for the tunnel’s operation and maintenance.
Takes their time
Although work is well under way to produce the first tunnel element, one should not expect that the element will be finished immediately.
– It will probably only be over the summer. When it’s the first segment we produce, we have to make sure everything works as it should. That’s why we take our time to learn along the way, so that we can optimize the entire process. Once the workflows have really settled down, you can make such a segment in a week, says Jens Ole Kaslund.
Excavation and portal to come
Before the tunnel element can be sailed out and lowered into place, the last part of the tunnel channel at the very inside of the tunnel portal must also be excavated, and the tunnel portal must be ready.
The tunnel portal has just had a tunnel floor cast for an underground basin that collects water from the roadway, which is thus the first permanent part of the future Fehmarn connection.
