21.12.2023

Delivery of the first gripper tunnel boring machine on section CO5 Lyon Turin

The ELYOT consortium, with Eiffage Génie Civil as the lead contractor, received this morning at Herrenknecht AG in Schwanau, Germany, the first of the two tunnel boring machines that will be used on section CO5 of the new Lyon Turin railway line! In terms of its type - it is a gripper tunnel boring machine - its diameter of 10.43 m, and its length of 334 m, it represents a first in France!

This hard rock machine will excavate 18 km of one of the two tubes of the base tunnel, under 2,200 m of cover, in the Ambin massif, from the base of the descent in Villarodin-Bourget/Modane to 3 km beyond the Italian border. A cross-border construction site!

Whereas most segmental tunnel boring machines excavate and install their own lining, the gripper tunnel boring machine excavates and applies temporary support tailored to the encountered geology.

Behind it, a second machine called MSE or "Würm" (worm in French) ensures the completion of the final lining of the tunnel.

The choice of this type of tunnel boring machine is explained by the geology: relatively compact, homogeneous, and stable; it is also motivated by the considerable depth of the work to be carried out and the associated geotechnical phenomena.
 

Client: TELT Lyon Turin

ELYOT Consortium: Eiffage Génie Civil (lead contractor), Spie batignolles, Ghella, COGEIS S.P.A.

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