Underground laboratory – Chooz, France

Within the scope of the “Double Chooz” scientific experiment aiming to study the behaviour of neutrinos, the GUINTOLI – SOLÉTANCHE BACHY TUNNELS group of contractors built between 2011 and 2013 an underground laboratory on the site of the Chooz nuclear power plant in the Ardennes region of France on behalf of CEA and CNRS, and with project management by EDF. The detailed design was carried out by the TERRASOL (contract leader) – SETEC TPI group.

TERRASOL carried out the design of supporting structures for the laboratory access (trench – 90 m long, and access tunnel – 20 m² section, 145 m long), for the underground cavern (95 m² section, 30 m length) and for its vertical shaft required for the experiment (13 m excavation depth, 9.5 m diameter). The studies for the structures, excavated in shale/sandstone materials, combined a structural approach (analysis of the stability of blocks cut out by bedrock fracturation) and finite element calculations in an equivalent elasto-plastic environment (estimation of deformations and stresses using 2D and 3D modelling).

Terrasol’s achievements :

TERRASOL performed the design of the laboratory access, the underground cavern and the vertical shaft.

PERIOD :  2011 - 2012
Maître d'ouvrage : CEA / CNRS
Maître d'Oeuvre : EDF
Client : Solétanche Bachy Tunnel
Main specifications :  

  • Descenderie de 145 m de long (section 20 m2);
  • Caverne de 30 m de long et 95 m2 de section
  • Puits vertical de 13 m de profondeur et 9,5 m de diamètre.