![]() ![]() ![]() A car traveling over the span is actually suspended 890 feet (271 meters) above the valley. In reality, the highest point of this cable-stayed bridge is taller than the Eiffel Tower by 62 feet (19 meters) and only a little bit shorter than the Empire State Building (1,250 feet or 381 meters tall, if you're wondering). ![]() Et voila - the Millau Viaduct, a massive bridge that opened in 2004 to carry the A75 motorway south to Beziers. Now, finally, picture lining up six more similar towers and stringing a roadway across the valley. Now imagine setting the tower down in the Tarn Valley, a deep gorge surrounded by high, rolling hills near the town of Millau, France. Now imagine tearing the tower from its moorings and carrying it southeastward, through the Massif Central region of France to the CĂ©vennes Mountains. The Eiffel Tower, which looms over the Paris skyline, measures 1,063 feet (324 meters) high from its four-footed base to the tip of its flagpole. As one arch lowers, the other rises to act as a counterbalance. When the bridge needs to move to its "up" position, eight electric motors tilt both arches as a single, rigid structure. The other arch sits at a 90-degree angle to the first, with cables strung between the two to provide support for the deck. In its "down" position, one arch forms the deck of the pedestrian and cycle path. The bridge is made up of a pair of steel arches. The winning design solved the problem, not with a bascule-type system, but with a never-seen-before tilting mechanism. The new structure had to allow ships to pass underneath without blocking the view of other nearby bridges or interfering with cultural activities taking place on either bank. This was the challenge facing engineers when officials in Gateshead, England, announced a contest in 1996 to design an innovative cycle and pedestrian bridge to span the Tyne River. They open quickly and efficiently but aren't the most elegant pieces of architecture. In a bascule bridge, one or two pieces of the bridge deck, known as leaves, swing up to provide clearance for boat traffic passing underneath. If it lasts as long as expected - 100 years - it should have a long time to pay for itself. Commuters have to pay 80 yuan, or almost $12, to cross it, but the toll fee is nothing compared to the bridge's price tag of 11.8 billion yuan ($1.72 billion). That's almost 25 times longer than the Runyang Bridge and nine times longer than Japan's pride and joy, the Akashi Kaikyo Bridge! The cable-stayed bridge snakes across the open ocean, carrying six lanes of traffic in both directions. It stretches a mind-boggling 22 miles (36 kilometers) across the Qiantang River at the Yangtze River Delta on the East China Sea. Today, the Hangzhou Bridge, which opened in May 2008 after nine years of planning and construction, holds the honor as China's longest bridge. Known as the Runyang Bridge, it was the country's longest bridge - for a while. More than 1,700 years later, in the Jiangsu Province, Chinese engineers completed a project that includes a 4,888-foot (1,490-meter) suspension bridge and a 2,575-foot (758-meter) cable-stayed bridge. 300 using bamboo cables, still carries pedestrians across the 1,000-foot (305-meter) Min River. The Anlan Bridge, a suspension bridge first constructed in A.D. The Chinese are not new to bridge building. ![]()
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