The official commencement of the excavation for the Italian section of the Mont Cenis base tunnel, a pivotal part of the Turin-Lyon railway line, began on December 18, 2023, in Val di Susa. Spearheaded by the binational UXT consortium—comprising Itinera (as the lead), Ghella, and Spie Batignolles—the project involves constructing the railway tunnel's two tubes spanning from Chiomonte to Susa, utilizing two Tunnel Boring Machines (TBMs). This consortium, awarded a 1 billion contract for the Italian works, initiated the groundwork for this significant infrastructure.
During the launch, the group unveiled their plan and signed key agreements, including the Lyon-Turin Business integrity and sustainability pact, and the Mission-S Charter, emphasizing workplace safety measures at the construction site. These documents, endorsed by TELT, the binational company overseeing the project on behalf of the Italian and French governments, pledge adherence to sustainable development principles outlined by the United Nations Global Compact across the entire supply chain.
The Mont Cenis base tunnel, spanning 57.5 kilometers, has already commenced construction on the French side, originating from the entry point in Saint-Julien-Montdenis, stretching 45 kilometers in France and 12.5 kilometers in Italy.
Following the completion of the contract for constructing interchange niches inside the Maddalena 1 tunnel in November, crucial for facilitating logistics for vehicles reaching the elevation where the two base tunnel tubes will be excavated, the new consortium took over the Chiomonte construction site.
The initial phases will involve site setup, preparations for excavation activities, assembling construction structures, installing equipment, finalizing the executive project, and ordering the two TBMs tasked with excavating towards the Susa adit.
Planned excavation activities encompass approximately 30 kilometers of tunneling work, including the two base tunnel tubes, the Maddalena 2 tunnel (the TBMs' starting point), connecting branches between the tubes, the Clarea safety site, and an artificial tunnel at the eastern Susa entrance.
Specifically addressing the excavation between the Clarea safety site and Susa, the plan involves employing two dual-mode TBMs capable of adapting their methods based on the terrain—employing rotating cutters for hard rock or modifying for softer soil like sand or gravel. These TBMs will adjust their approach to tackle a 1.5-kilometer stretch in Val Cenischia, where more fragile soil conditions prevail.
In addition to environmental protection measures during the works, the UXT consortium is dedicated to transforming the Chiomonte site into a "zero emissions" construction zone. This initiative involves minimizing emissions by utilizing renewable energy sources, implementing low-energy consumption technological systems, and deploying low-emission vehicles, including electric ones. Furthermore, they commit to offsetting any residual emissions through certified projects.
For further information click here, fr/11 and it/80 for the tunnelbuilder archive. Visit https://www.telt.eu/en/. 51/23.
