Strengthening the deck with additional prestressing
The project began in September 2017 by strengthening the deformed deck. The aim was to prevent the level of deformation from worsening further, rather than actually restoring the bridge’s initial geometry. Freyssinet installed two additional longitudinal prestressing tendons (27T15) and eight additional transverse prestressing tendons (4T15 S) in the first two crossbeams on each side of the deck. Access was required to the deck’s underside to anchor the cables. There were initially plans to provide access by erecting fixed tower scaffolding on the riverbanks. But Freyssinet ultimately set up a flying scaffolding system from the bridge deck to avoid encroaching on the footprint of the River Loire’s water levels.