The longest bridge in the world

China's Danyang-Kunshan Bridge is a record-breaking super structure, spanning rivers, lakes, swamps and cities.

Danyang-Kunshan Bridge seen from above. Photo: Wikimedia

Bridges come in all shapes and sizes, from the world's longest suspension bridge connecting Europe and Asia to a bridge woven from living roots in India. However, the Danyang-Kunshan Bridge in China holds both the titles of longest and second-longest bridge in the world, according to IFL Science .

Part of the Beijing-Shanghai high-speed railway, the Danyang-Kunshan Bridge in China connects Shanghai and Nanjing, making it the longest bridge in the world. This engineering feat stretches 164.8 km and crosses fields, rivers, lakes and even cities. Running parallel to the Yangtze River from its mouth in Shanghai, the bridge has an average height of 100 m, but because it was designed to allow ships to pass underneath, some sections of the bridge are as low as 150 m from the water.

Due to the length and the different terrain differences below the bridge, it is both a viaduct and a cable-stayed bridge in some sections. Viaducts are bridges supported by a series of towers or arches below, while cable-stayed bridges use tension cables running diagonally from the towers above the bridge. The Danyang-Kunshan Bridge is so long that a section of the bridge called the Langfang-Qingxian Viaduct is even considered the second longest bridge in the world at 114 km long.

The completion of the Danyang-Kunshan Bridge in 2011, just four years after construction began, transformed rail travel in the region by reducing the 4.5-hour journey from Ningbo to Jiaxing to two hours.

With a construction cost of up to 8.5 billion USD, or 1 million USD/km2, the entire bridge is made of about several hundred thousand tons of steel and supported by 11,500 concrete pillars. The section of the train running through Yangcheng Lake in Suzhou alone used 2,000 pillars. Despite the relatively rushed construction process, the bridge is also designed to withstand a series of natural disasters affecting the area such as earthquakes and storms as well as a direct collision of 300,000 tons from a naval ship. The estimated lifespan of the bridge is more than 100 years.

An Khang (According to IFL Science )

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