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Avrieux site

Telt - Suivi de Chantier
Telt - Suivi de Chantier
Base tunnel ventilation shafts
The construction site’s goal is the creation of four parallel vertical shafts. They will start at the bottom of the Villarodin-Bourget/Modane winze and will reach the surface in the territory of the Avrieux municipality.
500 metres deep and with a diameter of 5.2 metres, these shafts will be dug by Raise Boring Machines, a technology developed in the mining industry precisely for the mechanized excavation of narrow vertical shafts.
The characteristics of the site
The borers chosen to dig the four base tunnel ventilation shafts represent a solution able to maximize the safety of workers compared to traditional drilling methods; they also reduce the impact on the territory, thanks to the limited extent of the excavations. Seven caverns, each up to 22 metres high and 23 metres wide, will also be dug during the work. They will be used for the assembly of the borers that will excavate the base tunnel towards Italy. The excavated material will be transported to the exterior using the existing winze. The contract, worth about 220 million euros, has been awarded to the grouping of companies composed of VINCI Construction Grands ProjetsDodin Campenon BernardVINCI Construction FranceWebuild and Bergteamet.

Data key

250 workers

36 months of work

4 ventilation shafts

500 meters depth

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