The service facilities, located at a maximum distance of 800 m each, are technical facilities essential for the proper functioning of the metro, as well as for the travellers’ safety and comfort. They guarantee up to 4 functions: access for the travellers’ rescue and evacuation, ventilation and fume extraction, power supply and disposal of tunnel water.
The structure called “Des Acrobates” is located in Saint-Denis, in the heart of La Plaine district, and precisely in the public park bearing the same name, opposite the Fratellini Academy. It will be built completely underground, at a depth of 40 meters. Therefore, the structure will not have parts in relief and only the ventilation grille and the emergency and maintenance access hatches will be visible on the surface.
Following the preparatory works carried out in 2017, Trevi France set up the job site in the spring of 2018. Four-meters-high noise barriers were positioned on each side of the construction site - rue des Cheminots, Annie Fratellini and Federico Fellini, as well as in the Square des Acrobates park.
The works for the underground walls started in February 2019 and will last six months, before the commencement of the excavation works of the structure. At the end of the works, and after consulting the local residents, the square will then be redeveloped and refurbished. Trevi France is performing diaphragm walls in the job site, by means of hydromills and grabs. The diaphragms made with the Soilmec Tiger SC-90 hydromill have a thickness of 1200 mm and a depth of 53 m, while those made with the Soilmec SC-90 crane have a thickness of 800 mm and a depth of 23 m.