NEW TURIN-LYON LINE: CROSS-BORDER SECTION

NEW TURIN-LYON LINE: cross-border section

The new Italian/French freight and passenger link at the heart of the Mediterranean Corridor

The central portion of the new line is the 65 km long cross-border section between Saint-Jean-de-Maurienne (France) and Susa/Bussoleno (Italy), crossing the Alps through the Moncenisio Base Tunnel. This infrastructure has been constructed beneath impressive rock heights, reaching 2,200 metres, in a mountainous setting characterised by complex geology.

This Turin-Lyon line is a new freight and passenger train line that is 270 km long, of which 70% is in France and 30% is in Italy. This central portion of the TEN-t network's Mediterranean Corridor connects the Iberian Peninsula to Eastern Europe, crossing Italy via the Turin-Trieste main line.

Italferr, along with leading international engineering companies Systra France, Pini Group and SETEC, has been involved in planning the Turin-Lyon line for many years, and was appointed as the bi-national TELT - Tunnel Euralpin Lyon Turin promoter, following a tender procedure, tasked with Direction of Works for two of the four operations lots into which the base tunnel was divided: one in France and one in Italy. Overall, the extent of the works on these two lots accounts for 60% of the works required to construct the entire corridor.

The main task is the Moncenisio base tunnel, the longest railway tunnel ever built: one of the most impressive infrastructure works in Europe.

The double-barrel, single-track tunnel is 57,5 km long, of which 45 km is in France and 12,5 km is in Italy. Once completed, it will be the longest railway tunnel in the world.

SOME DESIGN DATA

A 162 km series of tunnels, made up of two parallel barrels, each about 57,5 km long and about 30 to 50 metres apart, connected by cross-linking passages approximately every 333 metres, for a total of 204 planned by-passes, and 4 inclined shafts.
Three Safety Sites have been designed along the route, from which it will be possible to exit via dedicated tunnels.
The system is rounded off with four ventilation shafts, each 500 metres deep and 5,2 metres in diameter.
Overall, the system involves constructing 162 km of tunnels, mainly formed using Tunnel Boring Machines (TBM), while the boring plan provides for simultaneous use of 7 TBM.

JOINT VENTURE OPERATING WORKSITES

JV S2IP made up of Setec (leader), Italferr, Systra and Pini for the CO6-6 Operating Worksite, French Side: the most impactful section of the entire Turin-Lyon base tunnel. This involves building about 27 km of double-barrel tunnel, with a complex safety post inside it, made up of a group of intersecting tunnels leading to the open air. The work is completed by logistical tunnels / caves, in which the 3 TBMs ordered for excavating this section will be assembled and moved.
JV IS2P made up of Italferr (leader), Setec, Systra and Pini for the CO-3-4 Operating Worksite, Italian Side. This involves the construction of about 12 km of double-barrel tunnel. The work is completed by a complex system of logistical tunnels to be used for handling traditional and mechanised boring and excavated material, especially related to storing waste material in the form of what are called green stones.

MAJOR CHALLENGES

Formation of an international team to deal with reference norms and technical aspects of constructing the tunnel in complex geological conditions and with the depth of rock overhead.
Operational management of worksites and technical solutions adopted to ensure safe, efficient works progress.
Management of environmental matters by means of constant dialogue with the competent authorities.
Advanced supervision and quality control to guarantee conformity of the tunnel.
Digitalisation and management of documentation.

GOALS

Controlling road traffic and promoting alternatives to road transport at the Italian/French border (transalpine freight traffic has doubled over the last 30 years).
Promoting trade along the Italian/French axis, within the TEN-T European network, via the Moncenisio Base Tunnel.
Upgrading the Turin Railway Junction.
Extension of the city's metro system to adjacent areas and the airport for passenger traffic.

The Turin-Lyon base tunnel is not merely a strategic piece of infrastructure, it is also a point of reference tunnel engineering. This project demonstrates the capacity for dealing with unprecedented technical and logistics challenges, by means of innovation, international collaboration, and sustainable construction practices.

The preparatory works on both the Italian and French sides along with a 10 km long line tunnel began in 2012 and were completed between 2017 and 2019. Work then began again in 2021 and 2022, based on the construction lots. Currently, completion of all works on the tunnel is planned for 2032.

TURIN-LYON