2005 / Footbridge over RER tracks
Location RER A, Bussy Saint-Georges, France
Client Epamarne, Commune de Bussy Saint-Georges
Architect RFR Paris
Engineer RFR Paris
Images RFR Paris
Scope of work For RFR - Concept design, Geometrical Consulting
The competition challenge was to design a footbridge over the rail track of a commuter train in the Parisian suburbs. The structure of the bridge is a lightweight timber truss which spans 45m. The specialty of the structure is its geometry It is based on a non-linear spiral curve, in which the density of members stands in relationship to the forces and moments of the truss. The spiral is very tight near the supports to transfer shear forces and wide in the central part of the simple beam structure. Unfortunately, the client was concerned about durability of the open-air timber structure. Existing examples could not convince him and so an ordinary concrete beam was announced as winning project at the final round.