The city of Świnoujście is currently building the new Świna Tunnel in order to improve transport links between the islands of Uznam and Wolin while connecting the coastal region more closely with the rest of Poland and the world. The project is expected to be completed in late 2022 and to be opened in 2023. An emergency tunnel is being built parallel to the two-lane 12-m-diameter tunnel. The road tunnel will span a total of 1.8 km and cross below the river Świna, a river connecting Szczecin lagoon with the sea and running between the two districts of Świnoujście located on the islands Uznam and Wolin. The Świna Tunnel will be Poland’s longest underwater tunnel yet. It will also be part of Poland’s S3 expressway connecting the north to the south over a span of 500 kilometers from the western part of Świnoujście on the island of Uznam to Lubawka in Silesia on the Czech-Polish border.
The Świna Tunnel is being excavated by a TBM (tunnel boring machine) over approximately 1.5 kilometers. Further tunnel sections will be completed using the cut and cover method, during which the excavation and construction are carried out under a cover cast on slotted walls. This construction method allows the excavation pit to be reinforced and the corresponding surface above the launch shaft on the islands of Uznam and Wolin to be used. fischer heavy-duty fixings are being used to reinforce the tunnel after the TBM work is completed. The chemical fixing systems and steel anchors fasten the reinforced concrete supporting structure. This required extreme anchor depths of up to 550 mm with rods measuring M16 and M30 in diameters in order to connect the reinforced concrete shell after the TBM operation. Platforms and struts for the launching shafts were additionally secured with the fixing solutions.
“Our products fulfilled the demands and requirements of the project. Our heavy-duty fixings allowed us to stand out from the competition and offered our client additional useful services”, emphasizes Oliwer Pietrzak, sales representative from fischer’s subsidiary in Poland responsible for the project. “We began offering our consultation services before the work started. Our services included planning and designing the fastenings in the process of working together with the construction firm, which allowed us to subsequently fully utilize our products’ potential. We also offered ongoing technical advice and support on the construction site”.
The professional fischer solution FIS EM Plus was used in particular. Together with its system components, this injection mortar permanently and safely transfers heavy loads into concrete even under the most extreme of conditions such as during earthquakes, in water-filled boreholes and in the event of fire. FIS EM Plus’s two European Technical Approvals (ETAs) and its ICC approval for the USA and countries in the Far East comprise fastenings in concrete in addition to post-installed rebar connections. FIS EM Plus also has an assessed service life (ETA) of 100 years. The Stuttgart engineering office IEA has furthermore certified that anchorages with the fischer FIS EM Plus have a service life of 120 years. It is the first injection mortar ever to be awarded this durability, an advantage during infrastructure projects like the Świna Tunnel which rely on a long service life.
The fischer FIS SB superbond mortar was also used together with system components. With its silane technology, the fixing system achieves a high bond stress resilience for a strong performance and a high level of security confirmed by its ETA for concrete and seismic loads. The variable anchoring depths of the injection mortar optimize the installation time and use of materials. Other mechanical anchoring solutions are also being used, including the fischer bolt anchors FBN II and FBZ as well as fischer concrete screws.
More than 50,000 fischer fixing solutions have been used on the Świna Tunnel project so far. The fixing expert will continue to support the client with products and services until the project's expected successful completion in summer of 2023.