Photos: TELT/Caroline Moureaux

EUROPE: The fourth of seven tunnel boring machines being used to excavate the Mont Cenis base tunnel has been formally presented to the Lyon – Torino project promoter TELT at Herrenknecht’s Schwanau factory in Germany, at a ceremony attended by Piemonte Region’s Transport Councillor, Marco Gabusi.

With a head diameter of 10·4 m and a length of 334 m, the of 3 200 tonne TBM will be deployed on contract C05 by the ELYOT consortium of Eiffage Génie Civil, Spie Batignolles, Ghella and Cogéis. It will excavate the 18 km central section of one of the twin running tunnels between the Villarodin/Bourget-Modane adit in France and the Clarea safety cavern in Italy. As such, it is expected to be the first machine on the project to cross the border between France and Italy.

The ‘gripper’ TBM has been designed for to cope with natural high temperatures as the tunnels pass through the Ambin massif, but must also withstand the pressure of more than 2 200 m of overburden, although the promoters note that the geology of this section is ‘relatively uniform’. The TBM will temporarily secure the excavated bore with a shotcrete coating, while a separate 650 m machine branded Würm will follow behind installing the final concrete lining segments.

‘This is the first of two TBMs that will cross the border, the most tangible symbol of our project: a railway that will unite Italy and France through the Alps, connecting our countries and Europe in a more efficient, economic and sustainable way’, commented TELT General Director Maurizio Bufalini. ‘Its twin will be ready in February, and then it will be the turn of the two Italian TBMs. We will then have no less than seven of them digging to complete the 57·5 km tunnel, the longest railway tunnel in the world.’