Tunnel Vranduk hole-through
By digging the last meters of the rock, today the right side of the Vranduk tunnel on the Vranduk – Ponirak subsection was breached. The length of the right pipe of the Vranduk tunnel is 312 meters, and the contractor is the consortium Azvirt L.L.C (Azerbaijan) and HERING d.d. Široki Brijeg (BiH).
Work on breaking the tunnel began in late March this year and was performed in three shifts. At the entrance to the right tunnel tube, the geology was more complex, while as the excavation progressed it improved. Most of the works were performed in category III using microreinforced concrete. At the same time, works were carried out on the preparation of fine leveling shotcrete, the foundation of the secondary lining, and in worse categories, the footing.
In the left tunnel pipe there are 108 meters left to dig out of the total length of 456 meters. This two-pipe tunnel was built according to the new Austrian tunnel method (NATM). Supervision over the execution of works is performed by the consortium DRI investment management d.o.o. (Slovenia) – DIVEL d.o.o. Sarajevo (BiH). Funds for the construction were provided through the OPEC Fund for International Development (OFID). The Vranduk – Ponirak subsection is part of the Poprikuša – Zenica north (Donja Gračanica) section, which continues to the Nemila – Vranduk subsection in the north and to the Ponirak – Vraca subsection in the south. The total length of the subsection according to the project is 5.3 kilometers. The facilities on the route include the Vranduk 1 and Vranduk 2 bridges, which are constructed using cantilever construction technology, and the Vranduk tunnel, as well as three smaller viaducts. The specificity of the route is the layout of the left and right sidewalks of the motorway due to the fact that the motorway stretches through very steep slopes. The motorway is mostly located in a notch, which is why a significant number of high retaining walls have been designed, which will be operated with reinforced earth technology.