Posted on October 7, 2024
Since January 2023, we have been building the piece de resistance of the Oosterweel junction in a large construction dock in Zeebrugge under the auspices of TM COTU. Now, the basic construction of the tunnel elements is completely finished. The next step? Preparing the transport to Antwerp, where we will immerse the eight elements to their final location in 2025.
Overall, up to 200,000m³ of concrete and 50,000 tonnes of steel were used for the realisation of the tunnel elements. Every part has a weight of about 60,000 tonnes and consists of two shafts for car traffic, a six-meter-wide bicycle shaft and an escape shaft. Together these elements form the Scheldt Tunnel, providing an additional crossing beneath the Scheldt and as such completing the Ring Road.
The works in the construction dock of Zeebrugge started in January 2023, with the first concrete pour for the tunnel elements. Now, more than a year and a half later and well on schedule, the concrete works have been finished with the last concrete pouring. In the coming months, the tunnel elements will be made waterproof and prepared for their journey to Antwerp. In the meantime, the construction dock itself is also being cleared out. When the last tunnel element will have left Zeebrugge, the new quay wall will be put into service and the extension of the port will be completed.
Gert Osselaer
Operational director at Lantis
“This last concrete pour marks an important milestone. During the past few years, many efforts have been made in this construction dock and progress has been impressive. Now we are working hard to achieve the next milestone, the towing of the tunnel elements to Antwerp. In the spring of 2025 this unique operation, that is being proficiently prepared by our contractor, will start.”
An amazing feat of technique in 2025
The operation starts with flooding the construction dock, adds Raymond De Kroon, Director Execution at TM COTU. ‘As soon as the tunnel elements are fully waterproof and ready to leave, the construction dock is cleared and flooded. The tunnel elements are equipped with ballast tanks to rise and immerse them in a controlled way. When we flood the construction dock, the ballast tanks are also filled with water. That way, the elements keep resting on the bottom, awaiting their leave. Then we rise them one by one by pumping the water out of the ballast tanks.’
Four tugs and one pusher tow the floating tunnel elements out of the construction dock. Through the North Sea and Scheldt, the elements make their way to the Doeldock where they can ‘park’ temporarily. During the immersing process, Scheldt water is pumped in the tanks, causing the tunnel element to sink slowly to the bottom.
‘We prepare the transport and immersing thoroughly. Designing and purchasing immersing material, drawing up action plans and carrying out risk analyses, thoroughly testing and monitoring, making arrangements with the shipping industry and maritime partners, but above all learning a lot about the Scheldt. It will be an amazing feat of technique, but also a very exciting moment.’
The Scheldt tunnel will be finished in 2028.Traffic will be able to drive through the Scheldt tunnel in 2030, cyclists will already be able to pass through the Scheldt tunnel as from 2028.
