References

The CDG Express project consists of creating a new 32-km direct line linking the Gare de l’Est railway station to Paris Charles de Gaulle airport.
This link is divided into 7 zones from Paris (A/B) to Roissy (H).

Terrasol is actively involved on zones A/B, C, D and F on behalf of SNCF and of several contracting companies, and was entrusted with numerous geotechnical design studies (G2), construction supervision missions (G4) or execution design studies (G3).

In the framework of the Zone C contract between the East and North rail networks, Terrasol is working with Setec on the global project management mission (MOE), bringing its geotechnical expertise to the different phases from design through to construction.

In the project phase, Terrasol has carried out all of the geotechnical studies for the project:

• analysis of the geotechnical data
• design of the temporary and definitive shoring walls with contiguous piles for the cut and cover tunnel under the CAP 18 industrial zone
• design of the deep foundations (piles and barrettes) for the future Porte de la Chapelle rail bridge
• design of the ballast-free track, as well as recommendations for dealing with the risk of gypsum dissolution.

After having contributed to the drafting of the tender documents and the assistance during tender assessment stage, Terrasol is participating in the construction management team.

In charge of the Visa mission and supervision of construction activities, Terrasol has a team of three engineers involved including a resident engineer assigned to the site since March 2020. We are in particular responsible of supervising the execution of IRS injections, cavity filling works, soldier pile walls, contiguous pile walls and deep foundation piles. The site currently on hold is awaiting the finalisation of several administrative procedures to reschedule the relaunching of the works.