Operation “100 hours” on Bezons flyover is a success 

Infrastructures Division

As part of the extension to suburban train line E (Eole), the teams from Eiffage Génie Civil, Tinel, Eiffage Métal and Eiffage Rail successfully shifted the tie-arch bridge on Bezons flyover for SNCF Réseau during Ascension weekend.

The grade-separated flyover will enable the line E tracks to pass over the existing railway line (Paris-Le Havre) without the trains crossing. Operation “100 hours“ mobilized 50 people, and a complete rail traffic flow outage was programmed during the works. The Group’s teams first had to raise the 96-metre-long, 2,000 t structure built in Eiffage Métal’s Lauterbourg plant and assembled below the railway line and move it to its permanent supports on a platform purpose-built over the rail tracks for the operation.

Hoisting the structure 6 m up in the air was managed with the help of four jacking towers, and it was moved by 2 groups of mutually coordinated self-propelled trucks over a curved length of around 35 metres. The structure was then taken up by the jacks located at the head of the piers, and very accurately positioned in terms of elevation and planimetry, with cementing of the permanent supports and load transfer.

The operation was scheduled until Sunday 2 June but was actually completed on Saturday the first, enabling our teams to return the tracks to SNCF Réseau where they joined those used to rest the railway equipment, before operations are resumed.

More information about Bezons flyover

Total length : 1 km

  • a tie-arch (or bowstring arch) bridge
  • a bridge over the Seine
  • engineering structures on both sides of the tie-arch
  • a footbridge for pedestrians and cycles linking Nanterre to Bezons, accessible to persons with reduced mobility 

     All in all, the flyover rests on 25 supports including 6 piers directly constructed in the Seine. Its structure is to comprise 7 decks which will support the future rail hub. The works are scheduled for completion in autumn 2021.

Photos Credit: Eiffage Branche Infrastructures