Tisséo, the public transport authority for Greater Toulouse have awarded two significant contracts for Line C of the Toulouse Metro. A joint venture (JV) consisting of Implenia (50%) and Demathieu Bard Construction (50%) has been awarded the contract for Lot 3. The project will last 57 months and has a total budget of €331.4M. Implenia’s share of the contract is worth approximately €166M.
Lot 3 includes drilling 3,814m of tunnel beneath a densely populated urban area, as well as civil engineering work for the construction of four underground stations at a depth of 24 to 39m, plus three ancillary structures. The joint venture has proposed using the “Variable Density Conveyor” method, an innovative tunnelling solution that will help cope with the challenges presented by different soil conditions. BIM (Building Information Modeling) is being used for planning and executing the project.
The joint venture’s bid placed particular emphasis on sustainability: the use of a fibre-reinforced concrete lining will keep the CO2 footprint of the project as low as possible, while the trees on the site will be protected and preserved throughout the entire construction period. In addition, 98% of the excavated material will be recycled.
Eiffage and NGE have been awarded the contract between the Laporte annex structure and the Raynal station (Lot 2) for a contract amount of nearly €590M (Eiffage’s share is 65% and NGE’s share 35%).
The consortium, of which Eiffage is the representative through its subsidiary Eiffage Génie Civil, will construct 8.416km tunnel and six stations and well as five ancillary structures at intersections and a connecting structure to the maintenance site. The contract also includes the construction of nine connection branches from the shafts to the tunnel.
Technical advances will also be prevalent on this section, including the implementation of two new-generation TBMs and the also use of fibre-reinforced concrete segments that consume less steel for 95% of the site. These will be manufactured in-house by the consortium thanks to a new factory in the Toulouse region. Carasol®, the soil characterization technique developed by Eiffage, will be implemented. It allows an analysis in 2 hours of the excavated materials against 3 to 5 days for traditional methods, thus limiting temporary storage and therefore truck rotations.
The project will start in the spring of 2023 after a 3-month preparatory phase. The handover of the infrastructure before fitting out is planned from the end of 2025, for Line C to be put into service in 2028