Among the 15,000 structures built in more than 60 countries by Matière, the Raymond Barre Bridge in the heart of Lyon is without doubt the most spectacular, both in its shape and its dimensions. At 260 metres long, 17.5 metres wide and weighing 3,400 tonnes, the bridge is distinguished by its asymmetrical bow-string type structure. A look back at one of the largest material construction sites of the decade.
Perpetuating the memory of a visionary statesman, the Raymond Barre Bridge is distinguished by its two large 150-metre long arches sloping outwards, which rise above the Rhône. Its wide central span, the longest in Lyon, draws a slanting movement and offers a unique view of the Confluence, especially at night.
When the asymmetry of a bridge becomes harmonious
In the city of Lyon, where there are already many bridges, this particularly elegant structure, with its meticulous design, is reserved for soft traffic (tramway, pedestrians, bicycles). Linking the Confluence and Gerland districts, its proportions have been skillfully studied, in harmony with the surrounding buildings so that it blends into the landscape as well as possible.
The Raymond Barre bridge designed by the architect Alain Spielmann uses the bowstring technique. Its special aesthetics – arches of varying dimensions, radiating cables and asymmetrical design
organisation – make it a refined work of art. It is distinguished by the finesse of its apron and the 10° inclination compared to the vertical of its two arches open to the sky.
An exceptional building site for a complex structure
The Raymond Barre Bridge is a structure with a complex geometry. From the very beginning of the construction site, our guiding principle is to respect the particularly tight deadlines, hence the corresponding material resources and the flexibility of our production tools to adapt to meet the schedules.
Far from being sufficient, it is above all human skills and values that are important. The Matière
Materials teams were keen to provide the best technical solutions at each stage: from the design of the metal framework, through the execution studies, to the installation of the deck, which required a high level of risk control.
Raymond Barre Bridge: a sum of technical challenges
In order to limit the impact on river navigation, the worksite has been set up on both banks of the Rhône. 70 people set up the west and central bays in the Edouard Herriot port area, about 1 km south of its location (this phase usually requires 10 to 15 people). Built on an assembly bench and not from welded reconstructed beams (PRS), each sheet is mounted on a template, each part has a different geometry.
Another challenge and probably the most spectacular and delicate operation to manage: the installation of the structure and the connection of the three spans to the bridge site. Transporting such a structure – 2,500 tonnes for dimensions of 170 metres x 30 metres x 20 metres – required exceptional millimetre precision.
The river transport and the descent on supports of the different parts of the bridge were organised in three stages by our teams involved:
1. The 150-metre-long central deck was transported by barge to the installation site.
2. The barge, moored to the banks of the Rhone River by numerous anchors, was pivoted in order to enter between abutment C0 and pier P1.
3. The central section of the bridge is then positioned in its final position, then lowered onto its supports. Raised to the right height, the bowstring is fitted onto the piers built to accommodate it.
Navigation was prohibited on the Rhône for the 30 hours necessary for the operation.
Inaugurated on 19 February 2014, the Raymond Barre bridge, which will have required two years of work. It is a new example of expertise in architecture and engineering obeying two golden rules: innovation and a taste for work well done.
The Raymond Barre Bridge in figures
4200 m3 of concrete
3050 t of structural steels
264 ml: length of the work
17.50 m: height of the arches in relation to the deck
3 spans: 36.90 m / 152.40 m / 50.80 m ;
Pile P1 in the middle of the Rhône, built in a cofferdam 15 m deep and with a surface area of 350 m².
1500 foundations on piles
40 months of work, including 11 months of manufacturing in the factory and 9 months of assembly work on the platform.
Cost: €27 million excluding VAT