The winning bid for the construction of the 1.5km long Sitina tunnel in Slovakia, should be announced this month, with the start of construction scheduled for next month.
The NATM-driven twin-tube tunnel will form part of the D2 motorway linking the Slovakian capital, Bratislava, and Brno in the Czech Republic. It is financed via an intergovernmental loan agreement between Slovakia and Japan, and three Slovakian/Japanese JVs have bid for the contract.
Slovakia is constructing 18 other tunnels, of which two are nearing completion. The 5km Branisko tunnel (T&TI November 1997, p20-22), near the town of Poprad on the D1 motorway running from west to east, should go into operation before the end of 2003, and the 605m long single tube Horelica tunnel, on the D3 route to Poland, broke through in June 2002 and is also expected to start carrying traffic at the end of 2003.
Exploration tunnels have recently been constructed on two other tunnels – the 2.3km long Ovciarsko and the 7.5km long Visnove.
The alignment of the Ovciarsko tunnel passes through complex sediments and central Carpathian paleogen, indicating complicated hydro-geological conditions. Full construction could start in 2006.
The single tube Visnove tunnel, which will pass through the Mala Fatra mountains, had an exploration tunnel constructed from both ends, breaking through in August 2002. Drill and blast was used from the west, and a 3.5m diameter TBM bored from the east. The tunnel highlighted ground water problems, and the plans to employ a 12m diameter TBM may give way to using drill and blast. Construction is expected to begin in 2004.
Another 14 tunnels are planned, with construction scheduled to start in 2004 or later.
This construction programme is a revised version of a plan that was introduced by the Slovak Road Administration in February 1996, to connect traffic routes to the European multimodal corridors.
Terraprojekt Bratislava is the client’s consultant.
