German contractor Hochtief has ordered a 3.1m diameter TBM from Lovat for construction of a 17.5km long water transfer tunnel in Munich, Bavaria. Tunnelling is scheduled to begin in May 2000
The tunnel will lie in a straight line between the villages of Oberhaching and Grub to the southeast of Munich and will be constructed in two drives from a central shaft with a grade of 1.5%. The anticipated geology consists of predominantly dense to very dense sandy gravel, clay and silt. A conglomerate of 10MPa UCS is expected along 40% of the tunnel alignment.
The TBM is equipped with a mixed face cutterhead having interchangeable rippers and disc cutters. The machine will also be equipped to erect a 4-piece expanded primary lining consisting of 1200mm long, 125mm thick precast concrete segments
The $44.8m scheme, known as the Hofoldinger Stollen Project, will complete the Munich Water Supply Tunnel, comprising the Mangfell Stollen and Hachinger Stollen Projects. Client and financier is the Stadtwerke Munchen. The whole project is scheduled to finish in April 2004.
