Vinci Construction Grands Projects consortium was awarded by the Tunnel Euralpin Lyon Turin (TELT) a EUR 220 million contract for preparatory works of the Avrieux ventilation shafts for the Lyon-Turin high-speed rail line.
The consortium comprises Vinci Construction subsidiaries Vinci Construction Grands Projets (lead), Dodin Campenon Bernard and Vinci Construction France (65%), alongside Webuild (33%) and Bergteamet (2%).
The work package 5A envisages the construction of four vertical Avrieux ventilation shafts to be excavated from the foot of the Villarodin-Bourget / Modane access tunnel. The shafts will be 500 meters deep and have a diameter of 5.2 meters. The works will be performed using raise-boring machines, comprising of mechanical excavators operating from the base of the future shafts, a technique which optimises work safety, costs and time. This technology was developed by the mining industry for vertical excavation of small-diameter tunnels.
The excavated materials will be removed from the shaft through the existing access tunnel.
The contract also includes construction work at the foot of the access tunnel required for proper operation of the shafts, in particular the excavation of 7 caverns up to 22 meters high and 23 meters wide that will subsequently be used to assemble the TBMs to excavate the base tunnel towards Italy.
The work involves preparatory work perpendicular to the future safety site at Modane, near the midpoint of the 57.5-km Mont Cenis base tunnel that will connect the international stations in Saint Jean de Maurienne, France, and Susa, Italy. The cross-border section of the Lyon-Turin mixed railway line extends over 65 km between Susa and St-Jean-de-Maurienne.
The project will employ up to 250 people over the coming 36 months.
By 2030, the 270 km Lyon-Turin high-speed rail line will remove replace 1 million heavy vehicles on Alpine roads resulting in a 3 million tonnes of CO2 reduction per year.