Millau Bridge

Millau Bridge (formally known as le Viaduc de Millau), is the tallest vehicular bridge in the world. Designed by the structural engineer Michel Virlogeux and British architect Norman Foster, it is the tallest vehicular bridge in the world. The steel-and-concrete bridge stretches 2.6 km (1.6 miles) long and rests on 7 pillars, and the tallest one reaching 1,122ft/375m — slightly taller than the Eiffel Tower and only 38 m (125 ft) shorter than the Empire State Building. It was formally dedicated on 14 December 2004, inaugurated the day after and opened to traffic two days later.

The bridge forms the last link of the A75 autoroute, (la Méridienne) from Clermont-Ferrand to Pézenas (to be extended to Béziers by 2010). The A75, with the A10 and A71, provides a continuous high-speed route south from Paris through Clermont-Ferrand to the Languedoc region and through to Spain, considerably reducing the cost of vehicle traffic travelling along this route. Many tourists heading to southern France and Spain follow this route because it is direct and without tolls for the 340 kilometres (210 mi) between Clermont-Ferrand and Pézenas, except for the bridge itself.

Built in 3 years, it provides an alternative route from northern Europe to southern France and Spain.

Foster’s winning proposal features seven equally spaced concrete masts, the tallest of which is 245 m (804 ft) high. These split into two when they pass through the road deck, creating a needle-like eye that flexes to accommodate expansion and contraction of the deck.
The masts are profiled to appear as slim as possible when viewed from the side, reducing the bridge’s impact on its surroundings. The concrete deck is suspended on steel cables 90 m (295 ft) below the mast tops, making it the highest road bridge in the world. The deck traces a shallow curve as it crosses the valley, allowing motorists to better appreciate the scale of the bridge as they drive across.

Unusually, the client (the Department of Transport and Public Works of France) insisted that engineering firms team up with architects to enter the design competition. Foster & Partners worked on the project alongside French engineering firm Eiffage, named after Gustav Eiffel who designed the Eiffel Tower.

"The whole thing looks impossibly delicate," Foster said in a telephone interview of what he called his "sculpture in the landscape" a 394-million-euro ($523 million) project financed by construction firm Eiffage. "It is a dialogue between nature and the man-made," he said.

For nearly thirty years prior to the construction of the Millau Viaduct, the A75 autoroute had remained unfinished. Before the bridge, a crossing of the River Tarn was provided by a bridge situated in the valley bottom, in the town of Millau. Millau was then known and dreaded as a ‘great black spot’ of motoring. Kilometres of congestion and hours of waiting to transit the town recurred each year with the great surge in traffic in summer months. These slowdowns meant that the advantages of the A75 were lost. The A75 was meant to be a positive example of spatial planning, a modern, direct highway entirely free along its 340 km (210 mi) length. As it was, the traffic from the autoroute brought pollution and danger to the town of Millau.

Design and construction of the bridge took a long time. In this region, climatic conditions are tough, with violent winds. Geological characteristics of the high plateaus of Larzac are peculiar, and, because the Tarn Valley is so deep, crossing is difficult. Different approaches were investigated, and all of them were found to be very technically demanding. Ten years of research and four years of implementation were required for completion of the Millau Bridge.

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