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November 1998, the Swiss people votes with a very large majority for the modernization of his rail network. Various projects are within the program. Among them, two alpine links under the Lötschberg and Gothard massif (see the workshop). 34.6 and 57 km (world record) respectively long, their service entrance is planned for 2007 and 2014 and their total cost is 12.5 billion Francs (8.1 billion Euros). The financing is ensured, more than half, by a royalty on the trucks traffic. First North-South fast links through the Alps, they will constitute two major elements for the development of the "France/Germany-Switzerland-Italy" axis connecting the Basle and Milan areas in 2 hour.

The Lötschberg tunnel, where we are here, will extend from Frutigen in the Kander valley (canton Bern) to Raron in the Rhone valley (canton Valais). It is based on a modern design using two distant tubes 9,4m diameter wide and 40m spaced. Safety will be guaranteed by connecting the tubes every 333m. Each tube being with single direction, the trains travelers will be able to reach a maximum speed of 250km/h. Initially, only one tube will be completely equipped and used. Each day 110 trains will take it and then, 300 in its final version.

The building started in 1999, is driven simultaneously from five working points distributed on the whole distance. The furtherance becomes thus less subject to the geological risks met. The two excavation modes, explosive and tunnel boring machine (140m length), are used according to the nature of the ground. The average progress is 15m a day. On the whole, 92 km of galleries will have been dug representing 16 million tons of rocks. A significant part of this volume is treated and then re-used like aggregate for concrete.

On the whole, 1600 peoples, various nationalities, work on the building sites. With 700m as average altitude, the galleries are until 1800m below the Alps. With such a depth, the temperature of the rock can reach 38°C and requires a permanent cooling. Dust, heat, moisture and noise thus constitute the difficult daily life of these men. As the trip in galleries to go to the working place takes up to 30 minutes, the breaks or meals are taken on the place...

This picture shows one of the two tests galleries intended to validate, in real size, the equipment and techniques used in the tunnel. It is accessible from the Mitholz site (Canton Bern). One see, in the foreground, the tracks and their sleepers on rubber bearings.

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