A specialised vessel will be used to help put in place 89 73,000t. precast concrete elements to form the 18km Fehmarnbelt Tunnel between Germany and Denmark.
A specialised vessel will be used to help put in place precast concrete elements to form the 18km Fehmarnbelt Tunnel between Germany and Denmark. 89 concrete elements will be used in total, with a standard width of 42m and length of 217m, and a weight of 73,000t. The concrete elements will be lined up in a trench on the seabed.
New Civil Engineer reports that this will be the second purpose-built vessel to be used on the Fehmarnbelt project. Earlier in the year, a multi-purpose pontoon was used in the process of applying a gravel tunnel lining to the trench.
The concrete elements are being cast on site on the Danish island of Lolland. Each element, which is fitted with a floatation device, will be tugged from the island to its destination. The specialised immersion vessel can be operated as two separate vessels, known as Ivy 1 and Ivy 2.
The two immersion pontoons will support the concrete element as additional ballast concrete is added to make the elements heavy enough to be immersed into the tunnel trench. The elements will be lowered in place by precision-guided steel wire winches. The equipment is currently undergoing a rigorous testing process.
Femern A/S construction marine manager Baris Nacar said: “It will require a steady hand and some highly advanced equipment to immerse the tunnel elements with the precision we require. Our Immersion Pontoon, therefore, has been specially built for this purpose.”
The Fehmarnbelt Tunnel will be a major cross-border rail connection between Germany and Denmark, and will form a key element in the Trans-European Transport Network (TEN-T). This is scheme that is designed to enable the efficient transport of people and goods around
EU member states and ensure good access to jobs and services.
The TEN-T comprises railways, inland waterways, shipping routes, tunnels and road links to airports, ports and terminals. It is tailored to create a joined-up and modern transport system that facilitates trade and travel across borders without any gaps or hold ups. This enables economic growth and social cohesion.
The Fehmarnbelt Tunnel is the world’s longest immersed tube tunnel, and will comprise of both road and rail connections. This will lead to faster rail journeys between Hamburg and Copenhagen and form a key connection between north and south Europe, benefitting trade and tourism in the region.
The tunnel will also ease pressure on the existing road network, promoting further economic growth in Northern Europe. The production of the concrete tunnel elements on Lolland is expected to continue until 2027, and the tunnel is scheduled to be completed in 2029.
The tunnel will form part of the Fehmarnbelt Fixed Link, which is part of a ‘green traffic corridor’ in Europe, and will feature electric trains and reduce other vehicular traffic.