The team has completed the tunnelling for Line b, the second automated metro line in Rennes, for regional authority Rennes Métropole and transport authority Semtcar.
After 38 months of operation, tunnel boring machine (TBM) Elaine, specially designed for the project, arrived at its exit shaft. Elaine has travelled about 8.5km deep underground, passing nine stations and four ventilation shafts. In total, the TBM, which is 82m long and has a diameter of 9m, installed 29,806 arch liners.
The JV, which is led by Dodin Campenon Bernard, also includes fellow Vinci subsidiaries GTM Ouest and Botte Fondations, along with Spie Batignolles TPCI, Spie Fondations and Legendre Génie Civil.
Line b will run between the south-west and north-east of the urban area and will serve 15 stations by 2020.
The Rennes network recorded 76.8 million trips in 2014; with the creation of Line b, traffic is forecast to reach 120 million trips in 2020.