The world's longest bridge

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

The Dan Duong - Con Son Bridge viewed from above. Photo: Wikimedia

Bridges exist 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 simultaneously holds both the title of the world's longest and second-longest bridge, according to IFL Science .

As part of the Beijing-Shanghai high-speed rail line, the Danyang-Kunshan Bridge in China connects Shanghai and Nanjing, forming the world's longest bridge. This engineering marvel spans 164.8 kilometers and crosses numerous 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 meters, but because it is designed for ships to pass underneath, some sections of the bridge are 150 meters above the waterline.

Due to its varying lengths and terrain differences beneath, the bridge functions as both an viaduct and a cable-stayed bridge in sections. Viaducts are bridges supported by a series of towers or arches underneath, while cable-stayed bridges use tensioned cables running diagonally from the towers above. The Danyang-Kunshan Bridge is so long that a section of it, known as the Langfang-Qingxuan viaduct, is even considered the second longest bridge in the world, measuring 114 km.

The completion of the Danyang-Kunshan Bridge in 2011, just four years after construction began, transformed rail travel in the region by reducing the journey time from Ningbo to Jiaxing from 4.5 hours to 2 hours.

With construction costs reaching $8.5 billion, or $1 million per square kilometer, the entire bridge is constructed from several hundred thousand tons of steel and supported by 11,500 concrete pillars. The section where trains pass through Yangcheng Lake in Suzhou alone uses 2,000 pillars. Despite the relatively rushed construction process, the bridge is also designed to withstand a range of natural disasters affecting the region, such as earthquakes and storms, as well as a direct collision with a 300,000-ton naval vessel. The estimated lifespan of the bridge is over 100 years.

An Khang (According to IFL Science )

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