A620 Foot and Cycle Bridge: When Aeronautical Profiles Inspire Girder’s Geometry

<p>This footbridge and its access ramps solve a major challenge for the Toulouse metropolitan area: to create an urban link for pedestrians and cyclists between the new district of Montaudran to the north, and the sports and aeronautical university colleges to the south. To create an inclusive, comfortable, and safe user experience, the crossing uses a subtle curved language for both the alignment and the steelwork geometry. Combined with the continuity of materials and railings, the route is legible from A to B, allowing users to easily understand where the crossing starts and ends. Inspired by the aeronautical profiles and strong history of the Toulouse Montaudran Aerospace site, the asymmetrical design of the main span frames users' views. The height of the beam varies along the length of the crossing, making it possible to open up or close off views, while at the same time ensuring that the bending and torsion moments generated by the span and the positioning of the supports on either side of the motorway are taken into account: a way of responding to the urban challenges of the site with a structural form that is just right, while at the same time optimising the tonnage of steel.</p><p>The paper describes in detail the architectural approach to the alignment and form, and the analysis model developed to assess the distribution of forces between the three different box girders which, together, give the overall shape of the steel girder. The dynamic analysis will be detailed, and the need of dampers will be explained.</p>