(CNN) -- The longest railway tunnel in the world was completed on Friday in Switzerland when the last two meters of rock were drilled through.
After 14 years of construction the 57 km (34 miles) of the Gotthard Base Tunnel in the Swiss Alps was finally completed when a giant drilling machine nicknamed Sissi cut through the last slice of rock to connect both ends.
After the final breakthrough, 50 miners carrying flags reprsenting the regions of Switzerland involved in the construction walked through the opening, Rahel Probst of AlpTransit Gotthard, told CNN.
"It all went very well, the drilling machine went through the rock and the tunnel was there," said Probst.
The tunnel is just over 4 km longer than the Seikan rail tunnel in Japan, which at 53.9 km had previously been the longest rail tunnel in the world.
Completion of the Gotthard Base Tunnel will cut the travel time between Zurich and Milan in Italy by 60 minutes to two-and-a-half hours and provide an easier and more economic route for heavy freight trains.
The tunnel -- which is in fact composed of two single-track tunnels -- cost $10.6 billion (£6.6 billion).
Since the first preparations for the tunnel were laid in 1996, over 2,500 workers have taken part in its building according to AlpTransit Gotthard, the company constructing the tunnel. It is due to be operational by the end of 2017.
Freight traffic in the entire Alpine region will grow by as much as 75 percent by 2010, according to a study by the EU Commission.
And according to AlpTransit Gotthard, the flatter route of the rail link "will allow fast, economical freight transportation."
"Only by upgrading its railway infrastructure can Switzerland meet the rising demand for freight transportation and the increasing needs of customers," according to an AlpTransit Gotthard statement.
COMMENTARY: This tunnel is one massive project.. Here's the hard data.
A cultural and trading barrier across Europe for centuries, the Alps remain so for transport. Implications have been marked in Switzerland as traffic has largely been in transit, rather than for Swiss producers or consumers. A motorway construction programme and the opening of the Gotthard road tunnel in 1980 greatly encouraged freight by road. General concern was joined by the shock of the multiple fatalities in the Gotthard and Mont Blanc road tunnel accidents.
To control adverse environmental effects, the Swiss constitution incorporated Protection of the Alps in 1994. Previously during 1992, Die Neuen Eisenbahn-Alpentransversalen (NEAT) or the New Rail Link through the Alps (NRLA) programme was approved for building two base tunnels. These were to be relatively level alignments at lower levels than previous tunnels through the massif on the BLS Lötschberg and SBB Gotthard routes.
Commercial operations through the partially fitted out 34.6km (21.5 mile) Lötschberg base tunnel began in December 2007.
The project
Controls on road freight were only deemed acceptable by surrounding EU countries if better rail infrastructure was created, notably at the Lötschberg and Gotthard pinch points. Even with access to dedicated Rollende Landstrasse (RoLa) trains for transit of complete heavy goods vehicles, both north-south routes had long, slow climbs at either side of tunnels at the respective summits and capacity was limited. The NEAT projects were aimed at removing the main limiting factors for the introduction of more, faster and longer trains on the key Rotterdam-Milan rail corridor.
A 100% Swiss Federal Railways (SBB) subsidiary, AlpTransit Gotthard, was established in May 1998 to deliver the project for the 57km (35.4 mile) Gotthard Base Tunnel. Construction is split into five sections, each with a designated consortium, from the north being: Erstfeld (ARGE AGN), Amsteg (ARGE AGN), Sedrun (ARGE Transco-Sedrun), Faido (ARGE TAT) and Bodio (ARGE TAT).
Other contractors are responsible for many other aspects of the project. The estimated final cost of the project was CHF9.4bn (US$9.0bn) for the Gotthard and 2.24bn for the related 15.4km (9.6 mile) Ceneri tunnel project further south on the route. These amounts exceed the original estimates, with the Swiss parliament approving reserves for uncertainties that included geological conditions, engineering issues and technological developments, the latter relevant due to the long project timescale.
By March 2010, about 94.7% of the planned 151.84km of tunnels, related galleries and passages were excavated.
Gotthard Base Tunnel infrastructure
Of slightly different length, the base tunnel will consist of two bores with two track crossovers and multiple interconnections for foot access between the bores. Entirely to the east of the current Gotthard line, access tracks to the new tunnel joining the present line at Erstfeld in the north and Bodio in the south. At a maximum altitude of 550m, the base tunnel is about 600m lower than the present line's summit and overall renders the Gotthard route no more challenging than many other parts of the SBB network.
"By avoiding the climbs,curves and spirals of the original Gotthard, the project will shorten the route by around 40km."
To speed the project, intermediate shafts were sunk to allow for simultaneous tunnelling on several faces, these points (Erstfeld, Amsteg, Sedrun, Bodio and Faido) to become integrated in the finished structure for servicing and emergency access.
Strict environmental control is in place for the work sites, the material supply chain and for the disposal of spoil.
The tunnels are mainly created by tunnel boring machines, with some use of drilling and blasting. The final section, 7.7km from Erstfeld, began in August 2007 and the breakthrough of the tube at Amsteg was carried out in June 2009. The final breakthrough of the GBT is scheduled to be done in November 2010.
Aside from the much higher speeds that the new alignment will provide, by avoiding the climbs, curves and spirals of the original Gotthard, the project will shorten the route by around 40km (25 miles).
As in the case of the Lötschberg, the old line will be retained for local passenger services, for general capacity and as a diversionary route: a noted part of railway tourism, it also provides an interchange with the east-west metre-gauge network via Göschenen.
Rolling stock
With freight most constrained by the present line and many trains needing double-heading for both the north and south ramps, an implication is a reduced need for motive power per train. Increased train lengths and weights will be possible through the near-level base tunnel, although in absolute terms the rising traffic demand will not diminish the need for freight locomotives.
Planning allows for advances in freight vehicles to allow for speeds up to 160km/h (100mph) through the tunnel. Longer trains and more of them allow for doubling the present freight capacity on the Gotthard route, much of which will be intermodal services, with Alp Transit setting the amount at around 40 million tonnes annually.
Domestic passenger services south to Chiasso and Locarno are likely to be formed in part by a next generation of Swiss coaching stock or units cascaded from elsewhere on the SBB network. Entering line testing in 2008, the ETR 610 from Alstom Ferroviaria is to become the flagship high-speed unit operating Cisalpino services between Switzerland and Italy. For Zurich-Milan, a 50min reduction to 2h50min by Cisalpino units is envisaged.
Signalling and communications
Following settlement of a legal challenge over the initial selection, the last major contract signed (CHF1.69bn in April 2008) for the Gotthard project was with the Transtec Gotthard Consortium to fit out the tunnel and approach tracks. Starting at the south portal, the work began in September 2009.
As installed in the Lötschberg, the Gotthard and Ceneri tunnels are to be fitted with ETCS/ERTMS Level 2 that obviates trackside signals. A leading adopter of the EC-sponsored system, non-EC Switzerland is advanced in the equipping of its rolling stock with the required equipment.
The future
Two aspects of the original project have been postponed indefinitely. The Porta Alpina deep level station planned as part of the Sedrun access point was shelved in September 2007 over concerns relating to cost, value and technical issues.
The 11km second phase of the Zimmerberg base tunnel on the Zurich-Zug section has also been dropped. Becoming the world's longest railway tunnel, commercial operation of the Gotthard Base Tunnel with scheduled train services is now planned to start no earlier than the end of 2017.
Courtesy of an article dated October 15, 2010 appearing in CNN World
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