Lyon-Turin works: About 100km still to be built

28 December 2021 Off By Marie-Christine MICHEL

At present, a little more than 30 kilometers have been excavated; the obstacles were sometimes unexpected. Already, there is a strong convergence in the coal field which required the implementation of specific methods.

Preliminary studies for the Lyon-Turin works

The twin-tube base tunnel and the descents are still far from being completed. In fact, there are still a little less than 100 km to be excavated in France. We are now entering the hard part! The 4 descents completed to date were the research axes for evaluating the main geological obstacles and testing the most effective technical solutions for the construction of the base tunnels.  Thus, the management of excavated materials (Villarodin-Bourget/Modane) and water (La Praz), the convergence of rocks under strong cover (SMP), and mechanized excavation (Chiomonte) were the subject of particular attention.

The Lyon-Turin worksite in progress

While the Puits d’Avrieux site is underway, it currently employs half of the workforce, i.e. about 350 people. However, this represents only a quarter of the number of people employed by 2025 (estimated at around 2,800 people).

On the Italian side, 7 of the 40 kilometers have been completed. The access roads to the cross-border tunnel have been definitively designed. The project on the French side is still under study.

Saint-Jean-de-Maurienne and the Grand Chantier approach

However, we already know that the capital of the Maurienne Valley will host the future multimodal station and the entrance to the future Lyon-Turin tunnel.

The Grand Chantier approach will allow the city to benefit from significant advantages. Indeed, there will be no base camp. All vacant housing to be rehabilitated will be able to receive subsidies of up to 80% of the amount of work carried out.

In return, the owners commit to renting the housing to the workers of the future work sites. A new dynamic on which the city intends to surf to renovate itself!

To get an overview of the work sites : vidéo

Photo: View from TELT platform

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