Zhaozhou Bridge
The Zhaozhou Bridge, still standing after 1400 years
Official name	趙州橋
Crosses	Xiao River
Locale	Zhao County in Hebei Province, China
Design	Open-spandrel stone segmental arch bridge
Longest span	37. Zhao County (Zhaoxian ( a historic town called Zhaozhou (赵州 in the past is located in Hebei 40 km southeast of the provincial capital Shijiazhuang, and 280 ( Postal map spelling: Hopeh) is a northern province of the People's Republic of China. China ( Wade-Giles ( Mandarin) Chung¹kuo² is a cultural region, an ancient Civilization, and depending on perspective a National A spandrel (less often spandril or splaundrel) is the space between two Arches or between an arch and a rectangular enclosure 37 metres (123 ft)
Total length	50. 82 metres (167 ft)
Width	9. 6 metres (31 ft)
Height	7. 3 metres (24 ft)
Beginning date of construction	595
Completion date	605
Coordinates	37°43′12.6″N, 114°45′47.7″E

The Zhaozhou Bridge (traditional Chinese: 趙州橋; simplified Chinese: 赵州桥; pinyin: Zhàozhōu Qiáo) is the world's oldest open-spandrel stone segmental arch bridge. A geographic coordinate system enables every location on the Earth to be specified in three coordinates using mainly a spherical coordinate system. Pinyin, more formally Hanyu pinyin, is the most common Standard Mandarin Romanization system in use A spandrel (less often spandril or splaundrel) is the space between two Arches or between an arch and a rectangular enclosure ^[1] Credited to the design of a craftsman named Li Chun, the bridge was constructed in the years 595-605 during the Sui Dynasty (581–618). Events By Place Europe Theudebert II becomes king of Austrasia. For the car see Peugeot 605. Events By Place Asia As a result of a quarrel between Numan III the Lakhmid The Sui Dynasty ( 581 - 618 AD and in the undertaking of other construction projects including the reconstruction of the Great Wall. Located in the southern part of Hebei Province, it is the oldest standing bridge in China. ( Postal map spelling: Hopeh) is a northern province of the People's Republic of China. A province, in the context of China, is a translation of sheng ( which is an administrative division China ( Wade-Giles ( Mandarin) Chung¹kuo² is a cultural region, an ancient Civilization, and depending on perspective a National

Name and location

The Zhaozhou Bridge is also known as the Safe Crossing Bridge (traditional Chinese: 安濟橋; simplified Chinese: 安济桥; pinyin: Ān Ji Qiáo), englished as the Anji Bridge and the Great Stone Bridge (traditional Chinese: 大石橋; simplified Chinese: 大石桥; pinyin: Dà Shí Qiáo). Pinyin, more formally Hanyu pinyin, is the most common Standard Mandarin Romanization system in use Pinyin, more formally Hanyu pinyin, is the most common Standard Mandarin Romanization system in use It crosses the Xiao River (Chinese: 洨河; pinyin: Xiào Hé, Jiao He) in Zhao County, approximately 40 km southeast of the provincial capital Shijiazhuang. Pinyin, more formally Hanyu pinyin, is the most common Standard Mandarin Romanization system in use The kilometre ( American spelling: kilometer) symbol km is a unit of Length in the Metric system, equal to one thousand Shijiazhuang ( literally "The Stones' Village" is a Prefecture-level city and the Capital of Hebei province, China It is named for the nearby Zhao County (趙縣), which was formerly known as Zhaozhou (趙州). Zhao County (Zhaoxian ( a historic town called Zhaozhou (赵州 in the past is located in Hebei 40 km southeast of the provincial capital Shijiazhuang, and 280

Construction

the elevation and arch-to-span ratio of a 1/4 circle arch bridge

The Zhaozhou Bridge is about 50 m long with a central span of 37. The metre or meter is a unit of Length. It is the basic unit of Length in the Metric system and in the International 37 m. It stands 7. 3 m tall and has a width of 9 m. The arch covers a circular segment less than half of a semicircle (84°) and with a radius of 27. In Geometry, a circular segment (also circle segment) is an area of a Circle informally defined as an area which is "cut off" from the rest of 27 m, has a rise-to-span ratio of approximately 0. 192 (7. 3 to 37 m). This is considerably smaller than the rise-to-span ratio of 0. 5 of a semicircular arch bridge and slightly smaller than the rise-to-span ratio of 0. 207 of a quarter circle. The arch length to span ratio is 1. 1, less than the arch-to-span ratio of 1. 57 of a semicircle arch bridge by 43%, thus the saving in material is about 40%, making the bridge lighter in weight. The elevation of the arch is about 45°[2], thus subjects the abutments of the bridge to downward force and sideway force.

The central arch is made of 28 thin, curved limestone slabs which are joined with iron dovetails. A dovetail joint or simply dovetail is a joint technique most commonly used in woodworking joinery. This allows the arch to adjust to shifts in its supports, and prevents the bridge from collapsing even when a segment of the arch breaks. The bridge has two small side arches on either side of the main arch. These side arches serve two important functions: First, they reduce the total weight of the bridge by about 15. 3% or approximately 700 tons, which is vital because of the low rise-to-span ratio and the large forces on the abutments it creates. Units of mass There are three similar units of Mass called the ton: Long ton (simply ton in countries such as the United Second, when the bridge is submerged during a flood, they allow water to pass through, thereby reducing the forces on the structure of the bridge.

Li Chun's innovative spandrel-arch construction, while economising in materials, was also of considerable aesthetic merit. An inscription left on the bridge by Tang Dynasty officials seventy years after its construction reads:

Later history and reputation

In the next 1400 years, the bridge survived at least eight wars, ten major floods and numerous earthquakes, the nearest of which being the 7. 2 degree Xingtai Earthquake in 1966. Yet, the support structure remains intact and the bridge is still in use. Only the ornamental railings have been replaced every few hundred years.

The Zhaozhou Bridge influenced the design of later Chinese bridge structures, such as the similar Yongtong Bridge near Zhaoxian in Hebei. ( Postal map spelling: Hopeh) is a northern province of the People's Republic of China. The Yongtong Bridge is a 26 m (85 ft) long stone segmental-arch bridge built in 1130 by the Song structural engineer Pou Qianer. The Song Dynasty ( Wade-Giles: Sung Ch'ao was a ruling dynasty in China between 960&ndash1279 CE it succeeded the Five Dynasties and Ten Kingdoms ^[3]

The intriguing design of the Zhaozhou Bridge has given rise to many legends. According to one legend, the bridge was built by a master architect named Lu Ban in a single night. Lu Ban ( fl 5th century BC) was a Chinese carpenter philosopher military thinker statesman and contemporary of Mozi, born in the State of Lu In another story, the bridge was put to the test by two immortals who crossed it at the same time and Lu Ban saved it by wading into the water and supporting the structure.

Although Ming Dynasty (1368–1644) authors compared the bridge to "a new moon rising above the clouds" and "a long rainbow hanging on a mountain waterfall"^[2], it later fell into obscurity. The Ming Dynasty ( or Empire of the Great Ming ( was the ruling dynasty of China from 1368 to 1644 following the collapse of the Mongol -led When Professor Liang Sicheng (梁思成) of Tsing Hua University rediscovered the bridge on a field exploration of ancient architecture in Hebei province, made detailed measurements, and published a report and drawing ("An Chi Ch'iao the Great Stone Bridge Chao Hsien, Hobei, Sui Dynasty AD 569-617, Li Chun Master Builder"), it became world famous. Liang Sicheng ( 20 April 1901 – 9 January 1972 was the son of Liang Qichao, a well-known Chinese thinker in the late Qing Dynasty National Tsing Hua University ( Taiwanese POJ: Chheng-hôa Tāi-ha̍k abbreviated as NTHU) is a university in Hsinchu City, Taiwan.

Zhaozhou Bridge was dedicated as an International Historic Civil Engineering Landmark by the American Society of Civil Engineers in 1991. The Chinese authorities nominated it for incription on the World Heritage List as having "a very important place in the world bridge building history". A UNESCO World Heritage Site is a site (such as a Forest, Mountain, Lake, Desert, Monument, Building, complex [3]

Footnotes

External links

• American Society of Civil Engineers: History and Heritage of Civil Engineering (select "Landmark Projects", then "Zhaoahou Bridge")
• Asian Research
• Chinaculture.org Site sponsored by the Ministry of Culture of the People's Republic of China