On 29 may 2024 Kolektor Construction and Euro-Asfalt completed excavation of the sixth and longest tunnel of the 2TDK project providing a second track between Divaca and the port of Koper. This will provide a modern and efficient railway link between the cargo port of Koper and existing rail network in Slovenia, and consequently the wider European rail network.
The Lokev tunnel (T1) is the first and longest tunnel on the railway line, located between Lokev and the Rosandra/Glinscica valley. Excavation work for its service tunnel is underway. The Lokev Tunnel (T1) is the longest tunnel in Slovenia: until now it was the Bohinj Tunnel with 6,327 m. The railway tunnel Karavanke is 7,976 m long, but more than half of the tunnel is in Austria.
The excavation works in the Lokev tunnel (T1) - started on 5 November 2021 from the Divaca direction and a year later from the Koper side. These have been particularly challenging due to the karst phenomena that have been exposed during the excavation. The largest ever karst cave has been discovered reaching 150 m deep and at least 450 m wide.
The 27.1km entire route of the second track of the Divaca-Koper railway line runs in seven tunnels Lokev (T1 - 6.714 m), Beka (T2 - 6.017 m), Stepani (T3 - 335 m), Tinjan (T4 - 1.949 m), OSP (T5-6 - 513 m), MLinarji (T7 -1.154 m) and Skofije (T8 - 3.808 m) which together with the service and exit pipes measure 37.4 km. The NATM (New Austrian Method) method was used for excavation.
The Second Track project is divided into three large packages. The first includes the construction of the Lokev (T1) and Beka (T2) tunnels, while Package 2 includes the construction of tunnels T3 to T7 without a service pipe and tunnel T8 with a service pipe, as well as the Gabrovica and Vinjan viaducts. Package 3 includes the construction of tracks and track devices, rolling stock, telecommunications devices, etc.
The Stepani (T3), Tinjan (T4), Mlinarji (T7) , Skofije (T8) and Osp (T5-6) tunnels have already been excavated, and in some of them the inner lining has already been completed. The Osp tunnel consists of two originally planned tunnels, which were combined in the later stages of the design into one tunnel, the special feature of which is its distinctly sloping location and low coverage in certain parts.
On the track of the 2TDK project, the appearance of the portals will be different. In the case of the first and last tunnels, the portal will be semicircular, which means in the form of an extended tunnel tube with a thickened rim. An example of such a portal is now being built on the Koper side of the Skofija tunnel (T8). All other tunnels will have a portals shaped like a polygon.
The second track project now requires the end of excavation of the 6683 m service tunnel of the Lokev (T1) tunnel, and of the main Beka (T2) tunnel with its 6042 m safety tunnel. The service tunnels have the same profiles as the main tubes. The construction contractors now only need to excavate 263.4 m of the 37.4 km of tunnels.
Despite the complexity and difficulty of the construction of the whole project, the project construction is on schedule and within the approved financial framework.Click here for a video, si/20 for tunnelbuilder archive. Visit https://drugitir.si/. 22/24.
