Breakthrough for Unterinntalbahn 6 Months earlier

On February 6th, 2009 Europe’s currently largest tunnel boring machine with 13 m diameter broke through the previously created concrete wall on the Lower Inn Valley Railway (Unterinntalbahn between Münster and Wiesing/A). With only 585 days of driving the 5.8  km long tunnel was broken through some 6 months earlier than scheduled. Porr-Tunnelbau GmbH’s managing-director Wolfgang Stipek: “It’s a more than impressive performance and was keenly observed by experts as no longer and bigger tunnel has been completed with a hydro-shield so far in Austria.” The task to be tackled represented a special challenge for the engineers as the entire tunnel was located more than 20 m below groundwater.
The hydro-shield machine specially developed for the Lower Inn Valley project weighs some 2,600  t. The 100  m long, mobile tunnel boring factory completed the almost 6  km long railway section from an underground shaft after starting up in May 2007. Towards this end the TBM advanced along the Inn Valley towards Innsbruck crossing the River Inn only a few metres below its bed. The cutterhead fitted with more than 300 tools pulverised around 90,000 lorry loads of rock during the drive.
After completion of the route, which altogether runs from Munich/D to Verona/I, trains will be able to run at speeds of up to 250 km/h.