Designed by Nicolas Esquillan, author of the CNIT at La Défense, the Félix Houphouet-Boigny bridge is a prestressed concrete structure that has experienced a notable deterioration since its completion in 1951. The current traffic is important: 2×2 roads run on the upper slab of the concrete hollow caissons, while rail freight convoys run inside. Expert reports have thus concluded that there is damage (shear cracking in the caissons and especially significant cracking of unreinforced concrete piles) and therefore there shall be a rapid intervention.
At the end of a call for tenders, it is the EIFFAGE-SPIE group variant which is selected. The rehabilitation project consists in the complete execution of new piles, including piers with jet grouting reinforcement, footings and news pier caps and new trimmers, to which the existing caissons loads will be transferred.
In partnership with SGI, setec tpi carries out the execution project verification services for the rehabilitation of the bridge.
Like any rehabilitation project, some parameters of the existing are not known with great precision: the 1951 project included inclined piles, reaching a depth of 70m, from which only the non-underground sections can be geometrically surveyed. setec tpi and EIFFAGE-SPIE work together to optimise the transition from the old to the new piles.
The existing caissons are reinforced by additional longitudinal prestressing. The boat-shaped layout retained makes it possible to improve the bending behaviour and to ensure a lifting of the shearing force.
Client : AGEROUTE
Partners : SGI (mandataire), terrasol
Contractor : EIFFAGE-SPIE
Period : 2016 – 2019