The new viaduct fills a missing link in the A75 motorway from Clermont-Ferrand to Béziers (and by extension Paris to Barcelona) across the Massive Central and will relieve a notorious road bottleneck through the old town of Millau at the bottom of the Tarn Gorge. The viaduct spans from the “Causse Rouge” plateau to the North to the “Causse Larzac” plateau to the South.
Foster and Partners’ design for the new viaduct was selected as the winner of a design competition.
The viaduct was designed in collaboration with Michel Virlogeux who conceived the basic engineering scheme. The design objective was to assure that the huge scale of the viaduct would appear as elegant and harmonious within the dramatic landscape setting.
In relieving Millau’s congestion the new viaduct will put the town “on the map” due to its dramatic design.
The viaduct has the highest elevated roadway in the world.
The piers to the underside of the deck have tapering concrete forms whose sectional profile has been “sculpted” to render them more elegant whilst responding to minimum structural requirements. Split form below deck provides structural stiffness between deck and pier whilst achieving lighter visual form.
It is a motorway with two lanes running in each direction with hard shoulders in case of emergencies. It will take approximately one minute to cross the bridge by car. There is a toll plaza to the North of the bridge.
The road deck slopes down at an angle of 3% from the South to the North.
The deck has a gentle plan curve (20km radius) allowing drivers to appreciate the overall structural
form as they approach and pass over the viaduct. The viaduct curves towards the town of Millau.
The approximate cost is 320 Million Euros (privately funded).
The viaduct was constructed by Eiffage. It took over 500 men just over three years to construct (October 2001 – December 2004).
Total viaduct length: 2.460m
Spans between piers: 342m
Deck height above river Tarn: 270m
Height of tallest Pier (P2): 245m
Height to top of tallest mast: 343m
Base dimensions of tallest pier: 25m wide, 17m long
Total construction weight: 242.000 tonnes (36.000 tonnes of steel, 206.000 tonnes of concrete)
Engineering Concept: Michel Virlogeux
Associated Architects: Chapelet-Defol-Mousseigne
Structural Engineers: EEG (Europe Etudes Gecti), Sogelerg, SERF
Landscape Architect: Agence TER
Design/Build/Operate Concessionaire: CEVM (Compagnie Eiffage du Viaduc de Millau)