The Millau bridge in France currently holds the record for the worlds tallest road bridge. At a towering 343m (1,125ft) at its highest point, it is definitely not for anyone afraid of heights. The bridge crosses the River Tarn and the valley of the same name and has been termed by some as “one of the most breathtaking ever built.” source The bridge was designed by architect Norman Foster who wanted it to have the “delicacy of a butterfly”… “A work of man must fuse with nature. The pillars had to look almost organic, like they had grown from the earth,” the world-renowned British architect said in an interview with regional daily newspaper Midi Libre.
The Bridge was constructed by French construction group Eiffage – that built the Eiffel Tower. The bridge was built to relieve the traffic bottlenecks that frequently occurred in the french town of Millau by connecting the two portions of route A-75 which is a major artery to the Mediterranean.
The bridge is also impressive for its embedded electronics, the structure contains 30 km of high-current electrical cables, 10 km of low-current cables, 20 km of fibre optics, and a total of 357 telephone jacks to allow maintenance workers to speak with the command centre and with each other while doing work on the bridge.
The structure also has some is state of the art safety infrastructure. There are sensors embedded in the pylons, deck, masts and stays. These sensors can detect the smallest movements in the structure and keep track of the both the structures resistance to, and degradation that occurs naturally overtime. The sensors are able to detect movements down to the micrometre, and are designed to take as many as 100 readings a second. In high wind conditions the structure is designed to constantly monitor the viaduct and its reactions. There are also, two piezoelectric sensors intended to gather traffic data, such as: the weight of vehicles, average speed, and density of traffic flow. The system is intelligent enough to categorise its traffic into fourteen different types of vehicle.The construction of the bridge was done with a number of segments prefabricated. The pylons were poured and constructed, and a couple of intermediate temporary pylons were also put up, then prefabricated deck pieces were pulled across the piers using satellite-guided hydraulic rams that moved the deck 600 mm every 4 minutes. The masts were then pushed out over the new deck, that was erected on top of the pylons, connected to the deck and the temporary pylons removed.
The construction of the bridge faced some opposition from international and local groups; including the WWF, France Nature Environment, the national federation of motorway users, and Environmental Action. Opponents argued that the bridge would never break even, even with the toll, they also argued that the bypass would negatively affect the town and its economy, and that the toll would cause motorists to bypass the bridge.
Some of these predictions have turned out to be very untrue, the town has approved more then 100 building permits in the 18 months following the viaduct’s construction, three of which are for new hotels, and the town has experienced and economic boom termed “the viaduct effect” and two other neighbouring industrial zones have also seen economic expansion that is attributed to the bridge and reduction in travel times.
Either way this Viaduct is a truly impressive structure and the pictures confirm it.