In primitive times, humans used naturally fallen trees, naturally formed Liang Shi or stone arches, rocks protruding from streams and vines growing on the banks of valleys to cross waterways and canyons. It is difficult to verify when humans purposefully cut down trees to build bridges or piled stones to build bridges. According to historical records, China had beam bridges and pontoons in the Zhou Dynasty (1 1 century to 256 BC). For example, around 1 134 BC, Wei River had pontoons in the Western Zhou Dynasty. In BC 1800, the kingdom of Babylon built a multi-span wooden bridge with a length of 183 meters. Ancient Rome built a wooden bridge across the Tiber River in 62 1 BC and a pontoon bridge across the Heller Strait in 48 1 BC. In ancient Mesopotamia, a stone arch bridge (with stepped arches) was built in the 4th century BC.
/kloc-before the 0/7th century, ancient bridges were generally built with wood and stone, and bridges were divided into stone bridges and wooden bridges according to building materials.
stone bridge
The main form of stone bridge is stone arch bridge. According to research, as early as the Eastern Han Dynasty (AD 25-220), stone arch bridges appeared in China, such as the unearthed portrait bricks of the Eastern Han Dynasty, engraved with arch bridge graphics. The existing Zhao Zhouqiao (also known as Anji Bridge), built in 605 ~ 6 17 with a clear distance of 37 meters, is the first hollow (open-shouldered) arch with a lower abdomen arch on the main arch ring. The arch rings and piers of ancient stone arch bridges in China are generally thin and light, such as baodai bridge, which was built in 8 16 ~ 8 19 years, with a total length of 3 17 meters, thin and flat piers and exquisite structure. In Roman times, there were many arch bridges in Europe. For example, from 200 BC to 200 AD, eight stone arch bridges were built on the Tiber River in Rome, among which the fabrizio stone arch bridge built in 62 BC has two holes, each with a span of 24.4 meters. In 98 AD, Spain built the 52-meter-high Al Bridge.
In addition, there are many stone arch bridges and waterway bridges, such as the existing Garde diversion bridge in France, which was built in BC 1 century. The bridge is divided into three layers, with 7 holes at the bottom and a span of 16 ~ 24 meters. In Roman times, arch bridges were mostly semicircular, with a span of less than 25 meters and a pier width of about one third of the arch span.
Hundreds of years after the fall of the Roman Empire, little progress has been made in bridge construction in Europe. 1 1 century later, pointed arch technology spread from the Middle East and Egypt to Europe, and pointed arch bridges began to appear in Europe, such as the avignon Bridge built by11188, which is a 20-span pointed arch bridge. The Thames Bridge built in Britain 1 176 ~ 1209 is a pointed arch bridge with a span of about 7 meters. Many arch bridges were built in Spain in the13rd century, such as San Ding Qiao in Toledo. Besides circular arch and secant arch, arch bridge also includes elliptical arch and flat arch. Pierre Bridge in France, which was built from 1542 to 1632, is an elliptical arch with seven holes and unequal spans, with a maximum span of about 32 meters. Oval arches were popular at that time. 1567 ~ 1569 A three-span flat arch bridge was built in Santa Trinita, Florence, with a height-span ratio of 1∶7. Bridges built in11~17th century, some of which have shops on both sides, such as Rialto Bridge in Venice.
Liang Shi Bridge is another form of stone bridge. Baqiao Bridge near Xi, Shaanxi, China, formerly known as Liang Shi Bridge, was built in the Han Dynasty, with a history of more than 2,000 years. From 1 1 to12nd century, dozens of large-scale Liang Shi bridges, including Luoyang Bridge and Anping Bridge, were built in Quanzhou in the Southern Song Dynasty. Anping Bridge (Wuli Bridge) was originally 2500 meters long with 362 holes, but now it is 2070 meters long with 332 holes. Some existing stone bridges in Dartmoor, England have a history of more than 2000 years.
wood bridge
Early wooden bridges were mostly beam bridges, such as the Wei Qiao built on the Weihe River in the Qin Dynasty, which was a multi-span beam bridge. The span of wooden beam bridge is not large, and the span of wooden bridge with legs can be increased. In the 3rd century AD, China built a "long 150 step" outboard wooden bridge at the junction of Anxi, Gansu and Turpan, Xinjiang. From 405 to 4 18, a cantilever wooden bridge was built near Linxia, Gansu, with a river width of 40 feet and a bridge height of 50 feet. The span of splayed wooden bridges and arched wooden bridges can also be increased. /kloc-Bassano Bridge in the 6th century was a splayed wooden bridge.
Wooden arch bridge
The earlier Telayan arch bridge was built on the Danube River in Hungary in 104, with a total of 2 1 holes, each with a span of 36 meters. Hongqiao built by China in Kaifeng, Henan Province, with a clear distance of about 20 meters, is also a wooden arch bridge, which was built in A.D. 1032. The Golden Belt Bridge built by the Japanese in Jinchuan River, a rock country, is a five-hole wooden arch bridge, which was built around 300 AD and is an independent Zen bridge of Dai Mangong, a monk in China.
The teacher helped build it.
There is a bamboo cable bridge made of bamboo strips in the southwest of China. The famous bamboo cable bridge is Zhupu Bridge in guanxian, Sichuan. The bridge has 8 holes, with a maximum span of about 60 meters and a total length of more than 330 meters. It was built before the Song Dynasty.
In ancient bridge foundations, the cofferdam method was adopted in Roman times, that is, the wooden boards were piled into cofferdams, and the bridge foundations and piers were built in them after pumping water. The foundation of the arch bridge on Thames River in England, which was built in 1209, was constructed by cofferdam method. But at that time, only manual piling was used to pump water, and the foundation was shallow. China 1 1 At the beginning of the century, the famous Luoyang Bridge threw stones all over the river at the bridge site. After keeping oysters on it for two or three years, the raft foundation was cemented, which was a pioneering work.
In 35 AD, during the reign of Emperor Guangwu of the Eastern Han Dynasty, the first pontoon bridge erected on the Yangtze River appeared between Yichang and Yidu.
The cable-stayed bridge in Shanghai was built in 1706, with a length of about 100 m and a width of about 2.8 m. It consists of 13 iron chains anchored on both sides. The Chinese Red Army of Workers and Peasants was famous when it crossed the bridge in the 1935 Long March.
Guanxian Anlan Bamboo Cable Bridge was built in 1803, which is the most famous bamboo cable bridge in the world. The total length is more than 34 meters, divided into 8 holes, and the maximum span is about 61m. The whole bridge consists of 24 5-inch thick bamboo cables, half of which are deck cables and half are stay cables.
During the Qin and Han Dynasties, Liang Shi Bridge was widely built in China. The longest preserved and most arduous Liang Shi Bridge in the world is Wan 'an Bridge, also known as Luoyang Bridge, which was built at 1053- 1059 Quanzhou, Fujian. This 800-meter-long bridge, with 47 holes in total, is located on the Haikou River with "rough waves and unknown water depth". This bridge is paved with rocks at the bottom of the bridge site, which is the beginning of modern mat foundation. The bridge foundation is glued into a whole by cultivating marine oysters, which is also a unique bridge-building method in the world. It is a brave breakthrough in the history of Chinese bridges to build such a long bridge under such difficult and complicated hydrological conditions nearly a thousand years ago.
The Hudu Bridge in Tanzhou, Fujian Province, built at 1240, is also the most amazing beam bridge. The total length of this bridge is about 335 meters, and part of Liang Shi is 23.7 meters long. Along the width, it consists of three Liang Shi, each of which has a Liang Shi width of1.7m and a height of1.9m and weighs more than 200 tons. This bridge has been preserved to this day.
The outstanding representative of ancient stone arch bridge in China is the world-famous Zhao Zhouqiao (also known as Anji Bridge) in Zhao County, Hebei Province. This bridge was built by Li Chun in the early years of the Sui Dynasty (around 605 AD). The bridge is an open-web round stone arch bridge with a clear span of 37m, a width of 9m and a height of 7.23m There are two abdominal arches with different spans on both sides of the arch ring, which can not only reduce the dead weight of the bridge, save materials, but also facilitate flood discharge. Zhao Zhouqiao's design concept and exquisite craftsmanship are not only second to none among ancient bridges in China. According to the research of bridges in the world, open-shouldered arch bridges like this didn't appear in Europe until the middle of the 9th century, which was more than 200 years later than China. Zhao Zhouqiao's sculpture art, including balustrades, watchposts, lock stones, etc., is worthy of being an artistic treasure in the treasure house of cultural relics because of its lifelike shapes and exquisite craftsmanship. The construction technology of stone arch bridge in China is