Grand Paris Express (Line 16/17 and 14-North): Detailled feasibility studies for LOT 1

Project description

Section 5 of the Grand Paris Express project includes two lines:

• Line 16-17 links Saint Denis Pleyel station to the Mesnil Amelot station. Within this, the section between Saint Denis Pleyel and the RER Bourget station is shared with line 16.
• Extension of line 14 northwards from Mairie de Saint-Ouen to Saint-Denis Pleyel.

The line 16-17 includes 9 stations, which will be constructed according to the following phasing:

• Saint-Denis Pleyel, La Courneuve, Le Bourget RER by 2023
• Le Bourget Aéroport, Triangle de Gonesse by 2025
• Parc des Expositions (above-ground station), Aéroport CDGT2 and Aéroport CDGT4 by 2027
• Le Mesnil Amelot by 2030.

The majority of the alignment will be bored with a TBM, with the exception of a 1.5km section which will be constructed on an embankment and a 3.5km section which will be constructed on a viaduct. The viaduct section uses a U-shaped deck-profile interrupted by various infrastructure elements which are required to cross obstacles, as well as covered sections. Elsewhere, it is planned to form a link tunnel between L16-17 and L15 either in cut-and-cover tunnels, or by tunnelling.
The line also includes various other civil engineering structures specific to the operation of the metro, including sidings and connections to a maintenance and storage yard.

Services provided

Update of the feasibility studies for section 5 – lot 1 (civil engineering) in order to integrate changes to the project: reduction in platform lengths, new line operating policies, optimisation of the phasing of the works and the construction methods to be used, as well as the costs. This required:

•  Studies and optimisation of the horizontal and vertical alignment including connections to the existing network
•   Optimisation of the tunnelled sections through the reduction of duel-bore tunnel in favour of a mono-bore solution
•   Optimisation of the station volumes and the methods of construction
•   Development of ancillary structures (emergency access and ventilation shafts) and optimisation of their geometry and their operation
•   Studies of the surface section of the line (5km on embankments and viaducts)
•   Redesign of the above-ground Parc des Exposition station
•   Environmental and financial management of the removal of the spoil produced from the worksite
•   Costing and cost management for the various phases to be commissioned (2023, 2025, 2027 et 2030 horizons)