The new Choisy-le-Roi bridge crosses the RER C suburban express railway lines serving passenger traffic to and from the southern Paris region. The 70 m long bridge has a traffic lane in each direction contained within wide footpaths to either side. Connecting the recently rehabilitated Port district with its housing, amenities, offices and Imprimerie Nationale workshops as well as Avenue Anatole France to the town centre, the bridge is an essential element in guaranteeing the success of this new district which, until now, has been cut off from the city due to its location between the railway lines and the River Seine.
The need for uninterrupted traffic flow – with the exception of a two hour break at night – represented the point of departure for the project’s technical and architectural design. It resulted in the bridge being designed as a straight double beam preassembled on one side of the railway lines which was then pushed out over the tracks in two operations, a solution that ensured that the overall span did not require any intermediate supports.
The infrastructure is contained within in a silvered perforated aluminium grid. This cladding, inspired by the wrapping of the Pont Neuf bridge by Christo and Jeanne-Claude, creates a memorable and poetic image without in any way interfering with the specifically technical aspects of the construction. The grid creates a pleat that provides the bridge with a fabric-like sensuality while simultaneously revealing the presence of the structure. This aspect is further emphasised by the green colour that is used, especially successful when lit up at night. The result is that the grid offers a highly distinctive atmosphere when crossing the bridge by car or on foot. The pleat envelops the structure, protecting, surrounding and framing the views at either end. The bridge presents itself as a uniting object, whether seen from above or from a distance. Its unambiguous technology provides a highly visible expression of the link created over the railway tracks and leading into the city. It is an approach that also places emphasis on the “poetry of useful objects”, a way of inserting itself into the city that avoids any need for formal gestures. The bridge presents itself as an icon, an efficient yet familiar object able to play a vital role in this rapidly changing urban environment.