The city of Soissons was equipped with a bridge connecting its historic heart with the district Saint-Waast, on the other bank of Aisne river. The current pedestrian footbridge was built post-war years in this location to replace a bridge from the 19th century destroyed during the allied bombardments.
Then financed by the United Kingdom – what explains its name – this footbridge was a reinforced concrete work with nice design but strongly damaged over time, what motivated the decision to replace it by a new work. The project of crossing is integrated into the global masterplan of the development of the Aisne river’s banks.
The goal is to return to the spirit of the pre-war bridge, with a more urban, wider and tenser work, placed in the continuity of the streets with which it is connected. The Project Team proposed a sober and elegant work, without visible structure under the deck. The project results from this architectural objective, while taking into account the double constraint of the access for disabled people and the Aisne river navigation regulations gauge.
The extreme thinning down of the deck, directly above the channel of navigation, was possible thanks to the implementation of two intermediate piles – the one in river and the other one on the towpath – and in the choice of the steel for the realization of the deck. The structural span is so reduced to 45 m for a total crossing of 62 m between both banks.
On the right bank, side Saint-Waast, the concrete pile is asserted: with its ellipsoidal shape, it rises up to the deck and bears it directly. On the left side, the other pile is rather hidden in the existing stone bank. The deck is supported by two V shape metallic profile very open and expressive, which allow to stiffen significantly the footbridge. The deck is formed by two side beam of variable height, linked by intermediate girders distant from 2 m.
They also support the metallic decking, itself recovered with a resin finish. The intrados of the footbridge is constituted by a continuous, smooth steel sheet, reflecting the movements of the water. The extreme delicacy of the work implied to make advanced dynamic studies. Continuous guardrails, fixed to the rear side of the main beams, have a constant height and follow the curvature of the footbridge.
From afar, these guardrails fade partially behind the variable height deck, seem visually thinner in the center and enhance the dynamic design of the footbridge. Continuous DEL lighting ribbon, fixed below the guardrails, provide a homogeneous and soothing illumination. Projectors integrated into stone banks enlighten the footbridge underneath: at night, the bow of the deck, the V bracing and the ellipsoidal piles are highlighted.
As a “belvedere” on Aisne river and on Soissons town, the new footbridge connects smoothly both banks and creates a new public place in the city. Its design fits into the urban landscape and establishes the starting point of the global Aisne banks renewal project. Source by Barthélémy Griño Architectes