Underground Construction

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Blessing Ceremony and Placing of St. Barbara Statue in Bancarevo Tunnel, Serbia
2012

 

Bancarevo Tunnel, E 80 Highway, Section Prosek–Crvena Reka, Serbia

Investor:Koridori Srbije d.o.o.
Designer:Institut za puteve a.d. - Beograd
Building Surveyor:IRD Engineering, Dubljanska 8, Beograd
Contractor:S u b t e r r a a.s.
Implementation period:15. March 2012 - 31. March 2017
Bancarevo Tunnel, E 80 Highway, Section Prosek–Crvena Reka, Serbia

The aim of the project is to construct a tunnel on the highway corridor No. 10, on the route E80 between cities Niš and Dimitrovgrad in Serbia. The tunnel is located in Suva Planina about 25 kilometers east of the city of Niš, in the mountains at an altitude of 500m above sea level.

Each of the double lane tunnel tubes has the length of about 700m. The tunnel tubes are interconnected by five connecting tunnels. The part of the contract is also the construction of the concrete road surface, the fire water supply, the drainage system and the installation of the technological equipment in the tunnels.

The rock massif is a combination of claystone, siltstone and loess with many geological faults. Therefore the tunnel classes 5, 5a and 7 were used and the frequent additional fixing was necessary. The crown of the tunnel must be secured with the “spile canopy” due to the frequent rocks fall. 

Due to the unstabile ground conditions and large geological overbreaks crown of the tunnel has to be secured by spile canopy.

The main part of the project is to dig pits for the tunnel portals. This takes place on steep slopes with a difficult access. According to the original project the excavations should exceed 200,000 cubic meters but they are not definitive. Due to the changes in an encountered geology it is necessary to backfill the excavated pits and to anchor them with the anchors 5 to 10 meters long (using about 3,000 pieces). Then the surface is strengthened with a shotcrete (2,000 cubic meters) and soil is then re-excavated. These measures will have a significant impact on the cost of the works (an increase of about 30%) and a year extension of the time of the construction.