A specialized vessel has been launched at the Crist shipyard to enable the construction of a so-called submerged tunnel to connect Denmark with Germany. The structure, built at the Gdynia shipyard, will be used to dump gravel on the seabed for the tunnel elements.
Crist Shipyard concluded a contract for the construction of a specialized vessel with the consortium of Femern Link Contractors (FLC) in September 2021. The FLC is responsible for the project and construction of the tunnel that will be submerged. Tunnel will provide constant connection in strait Fehmarnbelt.
The transport link will be contained the highway and rail line, including an 18-kilometer tunnel that will enable faster and safer traveling between Scandinavia and Europe, between ports Puttgarden in Germany and Rødbyhavn on the island of Lolland, Denmark. The tunnel link will enable train travel between Hamburg and Copenhagen to take less than three hours, which currently takes 5.5 hours.
For the construction of the tunnel necessary specialized equipment, which includes the facility under construction at the Gdynia shipyard. Crist will build a fully-featured multi-purpose vessel (barge), equipped also in a submersible drop device (so-called SDT, also constructed by Crist), which will be used to dump gravel evenly on the seabed for the submersible tunnel elements (submersible caissons).
– Unit hull will be 130.2m in length. ( The total length: 149 m, including transmission belts). The whole width will be 48 m. The unit will accommodate up to 19 people, it will have two gravel tanks, each up to 7,000 tons. The remotely-operated gravel dumping tool (SDT) will be lowered from under the bottom hull to 46 m below the waterline, where there will be layered foundations of gravel under the submerged tunnel. The combination of a high level of automation and state-of-the-art positioning technology will ensure accurate placement of the gravel foundations, the press release said.
The tunnel components will be transported and installed using submersible pontoons connected by a so-called crane truss. The pontoons can be used in various configurations to install both large and smaller tunnel elements. They were designed to work in the Ferhman lane area for the sole purpose of installing tunnel elements. The project will be equipped with generator sets, a mooring winch and lift system, a hydraulic system, and a range of other specialist equipment necessary for such a large and unusual project.
Crist Shipyard is already known for building unusual, innovative vessels. First, there was the self-elevating barge Zourite building a road over the seafront, i.e. a sea viaduct on La Reunion Island. The specialized self-elevating barge Zourite is the first of its kind in the world. The unit cost €80 million to build. The part made by Crist is worth 40 million euros, the rest is the cost of the specialized equipment installed on the barge. It was handed over to the shipowner in March 2016. Then there was the Marco Polo dock for the construction of caissons, which made it possible to build a flat development in the Principality of Monaco on the site of the bay.