Sidu River Bridge

The Sidu River Bridge (Siduhe Bridge, 四渡河特大桥) is a suspension bridge crossing the valley of the Sidu River near Yesanguan in Badong County of the Hubei Province of the People's Republic of China. The bridge was designed by CCSHCC Second Highway Consultants Company, Limited. and built at a cost of 720 million yuan (approximately US$100 million). Wang 2009, p.65. "The bridge cost the Chinese government 720 million yuan (roughly U.S.$100 million). The design was engineered by CCSHCC, Second highway Consultants Company, Limited;which is based in Wuhan, China." It opened to traffic on November 15, 2009.

Geography

The bridge is part of the new G50 Huyu Expressway that parallels China National Highway 318, an east-west route between Shanghai and Chongqing,
crossing the wide belt of mountains that separate the Sichuan Basin from the lowlands of eastern Hubei. The Yangtze River pierces the same mountain belt to the north, forming the famous Three Gorges. The Yiwan Railway, completed in 2010 and running parallel to the highway, has been described as China's most difficult to build and most expensive (per km) rail line.

The bridge spans a valley of the Sidu River (a left tributary of the Qingjiang River), and superseded the Royal Gorge Bridge and the Beipan River Guanxing Highway Bridge as the highest bridge in the world until it in turn was surpassed by the Duge Bridge in 2016.

Design and construction

The bridge's design includes H-shaped towers, a truss-stiffened main span, and unsuspended side spans. The Warren-type trusses were constructed in 71 sections with the largest section weighing . The trusses are tall and wide.

The height measurement from the bottom of the gorge has been reported as by Eric Sakowski, by Chongxu Wang, and by Yinbo Liu.It is not clear that these sources are measuring to the same point on the bridge. Some may be measuring from the bottom of the gorge to the top of the towers, explaining some of the discrepancies in the numbers reported. In addition to the numbers reported by Sakowski, Liu, and Wang, there are additional less-reliable sources on the internet that report the height at 560 m.

The first part of the suspension cable installed, a rope known as the ''pilot cable'', was the first-ever to be placed using a rocket. Conditions at the bridge's location would not allow the use of boats or helicopters, which have previously been used to string the first cable. The rockets carried the pilot cables across on October 6, 2006 and resulted in time and cost savings. Wang 2009, p. 80. "The installation of the main cables began with the placement of a pilot cable." "Conventional methods for placing the pilot cable ... could not be used." "An innovative cable placement method using a military rocket was developed." "On October 9, 2006, two rockets were fired to take the two 1,300 m ropes made of chinlon, a highly elastic yarn, over the canyon, a distance of roughly 1,100 m." "The entire process was completed in a short period—perhaps 10.00 seconds—and the cost savings were significant."

The main suspension cables are made of 127 parallel wire strands bundled into a hexagonal shape (127 is the sixth centred hexagonal number). Each strand is made of 127 wires (also making a hexagonal shape so that there is a total of 16,129 wires in each of the two main suspension cables). Each cable can hold . Wang 2009, p. 79. "Prefabricated Parallel Wire Strand (PPWS) was used for the main cable. Each main cable consisted of 127 parallel wire strands arranged in a hexagonal shape, and each strand is made from 127 galvanized high-strength steel wires, each 5.1 mm in diameter, also arranged in a hexagonal shape. The maximum tension force that the cable can bear is 191,960 kN."

Notes

References

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External links

*{{Commons category-inline, Siduhe Bridge

Suspension bridges in China
Bridges in Hubei
Bridges completed in 2009
2009 establishments in China
Badong County