Wienerwaldtunnel

The Wienerwald Tunnel is a 13.35-kilometre-long railway tunnel near Vienna in service since 9 December 2012 passing underneath the northern part of Wienerwald between Gablitz and Mauerbach. It is part of a new 250 kilometres per hour section between Vienna and St. Pölten which is part of the Western Railway .Construction detailsAs part of the ongoing four-tracking of the Westbahn, Austria's most important rail corridor, the doubling of the Vienna — St. Pölten section gets two new tracks on an alignment without high grades and fit for high speeds, deviating far to the North of the original line. The single biggest superstructure is the tunnel to cross the Wienerwald mountains.11 km of the Wienerwaldtunnel from its western portal is built as a bi-tube tunnel (a tunnel consisting of two connected single-track tubes), the rest is a two-track, single tube section. The digging of the single tube section started in autumn 2004, using drill-and-blast and excavator methods. The boring of the bi-tube section started a year later, using two TBMs. Tunnel boring was finished two years later, structural work was completed in February 2010, track construction (using slab track) started in the summer of 2010.The Wienerwaldtunnel is only one part of a tunnel complex: at the eastern (Vienna) end, it ends in an underground junction with a 2.2 km tunnel carrying two extra tracks for the old Westbahn (which is already in service since December 2008), and direct tracks across the junction continue in the Lainzer Tunnel (a 12.3 km long two-track single tube tunnel that is also in construction for a 2012 opening), the Lainzer Tunnel itself branches before its eastern end towards two portals. The altogether 26 km Wienerwald/Lainzer Tunnel enables trains travelling along the Westbahn to call at Vienna's new main station, and is Austria's longest tunnel.