Final Hydraulic Launch Successfully Closes last Gap in the Millau Viaduct in the South of France
Friday May 28th, 2004 the Millau Viaduct in the South of France reached a great historic moment. The last hydraulic launch of a series of 18 launches closed the last gap in the magnificent viaduct, connecting the North and South valley of the river Tarn near Millau in France, creating the most direct and efficient route between Paris and the Mediterranean coast.
After 32 months of construction and 18 hydraulic launches of the steel deck, the remaining gap is closed. Currently the two decks are being permanently clamped. The official opening of the viaduct is expected in January 2005.
Since the first hydraulic launch of the deck, February 27th last year, another 17 launches -12 from the South side and 6 from the North side of the valley - were needed to move the deck the 2,460 meters to bridge the Tarn valley. Each of the 7 piers and 7 temporary piers were equipped with ingenious high-pressure hydraulic launching devises to move the 36.000 tons of steel.
The Millau Viaduct, with its height of 343 meters, is designed by the English architect Lord Norman Foster, now is the highest bridge in the world. The search for an aesthetic construction led Michel Virlogeux to adopt the principle of a multi-stayed viaduct, consisting of slender soaring pillars and a very light deck, just touching the valley at only seven points.
Eiffage was selected to carry out this project combining the techniques of concrete with those of steel. Enerpac provided the Hydraulic Integrated Solutions to lift the temporary piers, needed for additional stability, and the launching of the steel deck of almost 2,5 km length.
Total length of the deck: 2.460 meters
Number of piers: 7
Shortest piers: 77 meters
Highest piers: 240 meters
Height of the pylons: 87 meters
Number of stays: 154
Thickness of the deck: 4,20 meters
Width of the deck: 32,05 meters
Total volume of concrete: 85.000 m3
Weight of the metal structure: 36.000 tons