Gotthard Base Tunnel

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The new Gotthard Base Tunnel together with the Zimmerberg Base tunnel form the northern part of the Gotthard axis of the Alptransit project(yellow: major tunnels, red: existing main tracks, numbers: year of completion).
The new Gotthard Base Tunnel together with the Zimmerberg Base tunnel form the northern part of the Gotthard axis of the Alptransit project
(yellow: major tunnels, red: existing main tracks, numbers: year of completion).

The Gotthard Base Tunnel (GBT) is a railway tunnel under construction in Switzerland. With a planned length of 57 km (35 miles) and a total of 153.5 km (95 miles) of tunnels, shafts and passages planned, it will be the longest tunnel (of all railway and road tunnels) in the world upon completion, ahead of the current record holder, the Seikan Tunnel (connecting the Japanese islands of Honshū and Hokkaidō). The project is designed to feature two separate tunnels containing one track each. The tunnel is part of the Swiss AlpTransit project, also known as New Railway Link through the Alps NRLA which also includes the Lötschberg Base Tunnel between the cantons of Berne and Valais. Like the Lötschberg tunnel, it is intended to bypass winding mountain routes and establish a direct route suitable for high speed rail and heavy freight trains. On completion it is expected to decrease the current 3.5 hours travel time from Zürich to Milan by one hour. The two portals will be near the villages of Erstfeld, Canton Uri and Bodio, Canton Ticino.

Completion has been projected for 2015 but due to delays the tunnel may not be completed before 2017.[citation needed] Moreover, according to a TSR programme, Temps Present aired on 25 May 2007, rail links with the Italian network are far from assured, due the pressure on trains transporting cargo to avoid the Milanese conurbation in favour of passenger transport.

Nearby are two more St. Gotthard Tunnels: the 1881 railway tunnel and the 1980 road tunnel.

Contents

[edit] Background

Intermodal train on the current Gotthardbahn in the Biaschina Gorge; truck on viaduct heading towards Gotthard road tunnel.
Intermodal train on the current Gotthardbahn in the Biaschina Gorge; truck on viaduct heading towards Gotthard road tunnel.

The route over Gotthard Pass or one of its tunnels is one of the most important passages through the Alps on the north-south axis in Europe. Traffic has increased more than tenfold since 1980 and the existing road and rail tunnels are at their limits. In order for a faster and flatter passage through the Swiss Alps, the Swiss voters have decided to build this tunnel cutting through the Gotthard massif at nearly ground level, 600 metres (≈1980 feet) below the existing railway tunnel. On the current track, the Gotthardbahn, only limited freight trains with a maximum weight of 2,000 tons using two or three locomotives are able to pass through the narrow mountain valleys and through spiral tunnels climbing up to the portals of the old tunnel at a height of 1,100 meters (≈3,600 feet) above sea level. Once the new tunnel is completed, standard freight trains of up to 4,000 tons will be able to pass this natural barrier as easily as if the Alps did not exist. Because of the ever increasing international truck traffic, the Swiss voted on February 20, 1994 for a shift in transportation policy (Traffic Transfer Act, enacted on October 8, 1999). The goal of both the law (and the goal of the Gotthard Base Tunnel, which is one of the means by which the law will achieve its objective), is to transport trucks, trailers and freight containers from southern Germany to northern Italy and vice versa by train to relieve the already overused roads (intermodal freight transport and so called rolling highway where the entire truck is being transported), and to meet the political requirement of shifting as much tonnage as possible from truck transport to train transport, as required by the 'Alpine Protection Act' of 1994.

Passenger trains, on the other hand, will be able to travel as fast as 250 km/h (155 mph) through the new tunnels, reducing travel times for trans-alpine train trips by 50 minutes – and by one hour once the adjacent Zimmerberg and Ceneri Base Tunnels are completed.

Scheme of the Gotthard Base Tunnel, centrepiece of the New Railway Link through the Alps NRLA (green: excavation in progress).
Scheme of the Gotthard Base Tunnel, centrepiece of the New Railway Link through the Alps NRLA (green: excavation in progress).

[edit] Construction

AlpTransit Gotthard AG is responsible for construction . It is a wholly owned subsidiary of the Swiss Federal Railways (SBB-CFF-FFS). To cut construction time in half, four access tunnels were built so that the construction of the tunnel can start at four (now five) different sites simultaneously (Erstfeld, Amsteg, Sedrun, Faido and Bodio).

A tunnel system with two single-track tunnels is being built. The two rail tunnels are joined approximately every 325 metres (≈1070 feet) by connecting galleries. Trains can change tunnels in the two multifunction stations (MFS) at Sedrun and Faido. These stations will house ventilation equipment and technical infrastructure, and will serve as emergency stops and evacuation routes upon tunnel completion.

Construction site near Bodio.
Construction site near Bodio.
Wye junction at multifunction station Faido.
Wye junction at multifunction station Faido.
The TBM from Bodio has arrived at MFS Faido on September 6, 2006.
The TBM from Bodio has arrived at MFS Faido on September 6, 2006.
Scale model of the TBM S-210.
Scale model of the TBM S-210.
In the eastern bore near Amsteg.
In the eastern bore near Amsteg.

Access to the site where the Sedrun station is being excavated is quite difficult. The station is only reachable by a level access tunnel of 1 km from the valley floor near Sedrun, where at the end two shafts lead 800 m (≈2,600 ft) straight down to the base tunnel level. A project to construct a functioning railway station called Porta Alpina at this site was put on indefinite hold in September 2007.

[edit] Allocation of work

The contracts are being let in sections as follows:

[edit] Facts and figures

  • Length: 56.978 km (western tunnel) 57.091 km (eastern tunnel)
  • Total length of all tunnels and shafts: 153.4 km
  • Begin of construction: 1993 (sounding drills), 1996 (preparations), 2003 (mechanical excavation)
  • End of construction: 2016–2017
  • Commissioning: 2015
  • Total cost: CHF 8.035 billion (US$6.428 billion)
  • Trains/day: 200–250
  • Volume of excavated rock: 24 million tons (13.3 million m³ or the equiv. of 5 Gizeh-pyramids)
  • Number of tunnel boring machines (TBM): 4 (2 southbound from Amsteg to Sedrun, 2 northbound from Bodio to Faido and Sedrun, section from Erstfeld to Amsteg will also be built with TBM, maybe the same used for Amsteg-Sedrun)
    • Total length: 440 m (incl. back-up equipment)
    • Total weight: 3,000 tons
    • Effect: 5 MWatt
    • Max. excav. daily: 25–30 m (in excellent rock conditions)
    • Total excav. length by TBM: about 45 km
    • Manufacturer: Herrenknecht, Schwanau, Germany

[edit] References

[edit] See also

[edit] External links

[edit] Footnotes

Year   Month   Completed so far  % of the total 153.4 km
2004 July 52.34 km 34.1%
2005 June 74.59 km 48.6%
2006 June 94.10 km 61.3%
2007 June 103.67 km 67.6%
2008 March 108.02 km 70.4%
2008 April 109 km 71%