Millau Viaduct

The Millau Viaduct is a cable-stayed motorway bridge, built to complete the A75 motorway in France. The deck, 270m above the Tarn River, carries four traffic lanes on a total width of 32m.
From their base to 90m below the deck, the high-performance reinforced concrete piers rise as a single hollow shaft and then they are divided into separate parallel shafts. Pier P2 is the highest pier, 245m, ever built in the world. Above the deck, 87m high steel pylons support the eleven pairs of cables for each span.
The steel deck is continuous along its eight spans. It was prefabricated and put in position by launching consecutive lengths of 171m. Seven temporary steel piers were used during the construction.
The initial study in 1990 was performed according to French Standards. The final structure was designed following the French Standards, as imposed by the contract, while the temporary piers and the steel deck were designed for instability with Eurocode 3.