Since May 2018, Sefi-Intrafor has been involved on line 16 package 1 as sub-contractor for Eiffage Génie Civil group. The special works include the Saint-Denis Pleyel station project…
Stretching from Seine-Saint-Denis to the outer edges of Seine-et-Marne, line 16 will form a key part of the growing city’s transport infrastructure. This line, which will eventually connect 10 stations, is one of the most highly awaited for the 2024 Olympics as it will provide direct access to several major facilities. For package 1, Sefi-Intrafor is building two stations (Stade de France and Saint-Denis Pleyel) and two TBM access structures (OA 3320P TBM1 and OA 6401P TBM 2b) under the terms of an approx. €78 million, 24-month contract.
Designed as not only the biggest, but also the most interconnected (lines 14, 15, 16, 17 and RER D) and the busiest station on the emblematic Parisian project, Saint-Denis Pleyel station requires major special foundations works. And specifically, the works on the deep diaphragm wall box that will house the station’s infrastructure. But Sefi-Intrafor’s teams are also having to deal with ducts protruding both above and below the surface, set up behind soldier pile walls on piles. On top of that, there’s the foundations for the emerging building… and the works required for the line 15 TBM, featuring a both conventionally- and jet-grouted plug.
All this work has to be carried out on a cramped urban site featuring: to the north, a mixed-use neighbourhood (residential properties, businesses, and offices); To the west and south, an industrial, crafts and shopping area;
To the east, the Landy rail hub, which is an issue; To the south-west, the future station, which already required the demolition of part of a private corporate building… It was demolished during the diaphragm wall phase, meaning access to the site had to be shared…
Unprecedented issues due to the exceptional dimensions of this project, particularly working out how to set up 100-tonne integral piers and reinforce the load-bearing elements for them to be attached to (without being responsible for the construction surveys), saw Sefi-Intrafor’s teams put all their skills to use to develop new methods and take up the challenges on this site.
On the scheduling side, and given the challenges of organising the Olympic Games, there was significant pressure to get the works underway. The diaphragm walls are ongoing, and the goal is to complete the works in mid-November.
This will require the installation of up to 4 panels a week.
Overall, a team of over 100 will be working every day to make this project - which is exceptional in many ways - a success.
Client: Société du Grand Paris
Prime contractor: Egis-Tractobel
Contractor (civil engineering): Eiffage GC