Mengdong River Bridge

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Mengdong River Bridge
猛洞河特大桥
Yongshun, Hunan, China
790 feet high / 232 meters high
837 foot span / 255 meter span
2012


Another gorgeous gorge buster, the Mengdong River Bridge is one of 3 high river crossings on the new Zhang Hua Expressway that extends from Zhangjiajie city in the east to Chongqing Province in the west and to Jishou City in the south. The other 2 giant spans are the Lishui and Aizhai suspension bridges. The CFST or concrete filled steel tubular arch of Mengdong is a creation of Chinese engineers since they first used in 1990 and is now the common method to build steel arch bridges throughout China's western provinces, especially when crossing a deep gorge or ravine.

The eight large steel tubes that run along the underside of the Mengdong arch were initially hollow. Once the arch was closed, concrete was pumped into these tubes from the bottom up. Depending on the length of the span and the width of the bridge, different styles of tubing are used. For Mengdong, they adopted an array of single tubes spaced apart from each other. Other configurations include dumbbells with two tubes closely connected, a mix of a dumbbell and single tubes such as was done on the Beipanjiang River Railway bridge or a tight cluster of tubes known as “multiple contiguous”. Once hardened, the concrete solidifies and stiffens the arch, improving the compressive strength of the entire structure.

I was fortunate to visit the construction site along with 2 other bridge fans during a 2011 trip through western China. Our amazing tour included a walk over an incredible 400 meter long Tibet-style construction footbridge. Our movement across the bridge created some unusual oscillations and other odd motions that made it one of the most unique bridge crossings I have ever taken. The feeling is similar to the experience of walking over a tourist bridge like Canada's Capilano Bridge but with much longer and more sustained up and down "wave" motions.

Since Mengdong spans a reservoir formed by a dam just downstream from the crossing, the bridge is 217 meters from deck to full pool or 232 meters from deck to the old river surface which is the official height figure HighestBridges.com always uses. The temporary Tibet-style footbridge was 174 meters above the reservoir or 189 meters above the old river level making it one of the highest defunct footbridges ever built.



Mengdong River Bridge Elevation


Image by jt.rednet.cn


Image by Hunan.voc.com.cn


The amazing temporary footbridge set up for the construction of the new Mengdong arch bridge. This span was 570 feet above the reservoir and was more then 300 meters long.


Image by Michael Wu.


Image by Michael Wu.


Image by Michael Wu.


Image by Michael Wu.


Image by Hunan.voc.com.cn




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