Austria
Bosruck Tunnel: Breakthrough for 2nd Bore
The breakthrough of the second bore for the 5.5 km long Bosruck Tunnel designed for 2 lanes took place on August 11, 2011 after only 17 months of construction. It occurred 2.5 months earlier than scheduled in spite of tricky geology (in the Haselgebirge with anhydrite springs etc.). This was followed by the remaining bench and floor excavation, production of the invert with drainage and creating bays and installing the concrete inner shell followed by the units for the extinguishing water supply, lighting and ventilation etc. The new tunnel bore was produced via drill+blast in accordance with...
