Important Milestone in the Construction of the Fehmarn Connection: The First of a Total of 89 Tunnel Elements has been Cast
From Preparation to Execution – A Complicated Process
Patience is a virtue – especially when complicated designs, calculations, and processes must be transformed into reality.
Every beginning is hard, and the casting of the first element has indeed taken about 10 months, whereas it is expected that the elements can be produced in 9 weeks going forward.
“It has been a long and complicated task to cast such a large concrete structure, and it has now been demonstrated that technology and methods work well together,” says Henrik Vincentsen, CEO of Femern A/S in a press release.
Going forward, the elements can be cast at a completely different pace, precisely because meticulous data and know-how have been gathered in the process around the casting of the first element, and because all 5 production lines are now operational. Similarly, the casting process will be optimized as the workers accumulate more and more knowledge and experience.
A Great Achievement
There is also pride to be found at the executing consortium Femern Link Contractors (FLC) over the achieved milestone. “Casting a single tunnel element is a great achievement in itself, but we still have a long way to go. Nowhere else in the world are concrete elements of this size mass-produced, but that is exactly what we must master in the coming years. Our goal is to turn the exceptional into routine,” says FLC Director Sébastien Bliaut.
The fact that this is a GREAT achievement is emphasized by the size of each element. An element is 217 meters long, composed of 9 segments of 24 meters each. An element weighs 73,500 tons.
The Further Process
The finished element must now cure for 3-4 weeks before steel bulkheads and the ballast tanks that will ensure the element’s stability during submersion are mounted. Meanwhile, the production of the remaining 78 elements continues on 5 production lines, while a separate line produces an additional 10 special elements. According to the plan, the first tunnel element, to be mounted at the tunnel portal entrance, will be submerged later in the year.
