The arch bridge with natural stone as the main building material has a long history, and it is still being built in areas with rich historical materials of stone, but it is developing towards lightweight. The most famous secant arch bridge in the world is the first one in Zhao Zhouqiao, China.
According to the classification of structural materials, there are two main types of bridges: stone bridges and wooden bridges, which are divided into single-span and multi-span according to the number of spans, and arch bridges and beam bridges according to the structural types. Arch bridges are mostly stone bridges, and some of them are wood structures, which are called stoplog arch bridges. Beam bridges are also different from flat beams and cantilever beams. The former may be a stone structure or a wood structure, while the latter are both wood structures. On the deck of all bridges, you can build bridges, pavilions and other buildings to form a particularly beautiful image. This is the covered bridge. In a word, there are many types of bridges to meet the different needs of different occasions.
Bridges are often attached to small buildings, such as the permanent archway at the bridgehead, and the famous stone arch bridge in front of Qionghua Island in Beihai, Beijing, with a big and beautiful archway at both ends. Huabiao, Jingzhuang and Xiaoshi Pagoda are also commonly used in bridges, such as baodai bridge in Suzhou, Wuli Bridge in Quanzhou and Luoyang Bridge. Characteristics of stone arch bridges in China. /
1. has a long history (the earliest recorded stone arch bridge "Traveler Bridge" was built around 282 AD). It is almost everywhere (that is, it is numerous and widely distributed). It varies in size and form, and many of them are amazing masterpieces-diverse and outstanding.
Stone arch bridge is one of the three basic types of traditional bridges in China. Stone arch bridge system is diverse. The two bridges described in this paper are outstanding representatives of millions of stone arch bridges. For thousands of years, stone arch bridges have spread all over the country. With the development of economy and culture, they have made rapid progress. They are an integral part of China's splendid ancient culture and have won honor for the motherland in the world. Up to now, a large number of ancient bridges are well preserved, which can be said to be the historical testimony of the exquisite skills of bridge builders in past dynasties, and also show the wisdom and strength of the working people in China. An ancient bridge can stand the test of natural disasters and wars and has not been broken for thousands of years. It is a miracle that it has not only been preserved as a monument, but also maintained its inherent functions. Of course, it is also due to the hard repair of the past dynasties, and this repair activity often comes from the folk's love and protection of the bridge. There are many stories about this social fashion in the history of Chinese bridges, which is worth telling. China is regarded as an ancient country with many bridges. This historical concept and quantitative concept, as well as the intuitive impression that there are physical objects to follow, are all knowledge that needs to be involved in understanding Chinese stone arch bridges. If these vivid historical facts are removed, not only is the connotation empty, but what can one or two isolated bodies tell us?
Secondly, the stone arch bridge appeared late in the history of bridge development in China, but once it appeared, it developed rapidly, that is, after the modern railway and highway bridge engineering technology was introduced into China in 1880, it still maintained its vigorous vitality, and made great progress in combination with modern engineering theory and new building materials. The two bridges introduced in this paper have been in Zhao Zhouqiao for 1400 years, and Lugou Bridge has stood on the turbulent Yongding River for nearly 700 years. Both of them are majestic and solid, and they still maintain their original style, which can be used by heavy vehicles. It is rare in stone bridges at home and abroad. Zhao Zhouqiao's open-shouldered creation was seven centuries earlier than that of the West. The reason why it can last for a long time shows that the design and construction are scientific. Another example is the shallow foundation and short abutment in Zhao Zhouqiao. Many modern engineers were surprised because it was unscathed after many earthquakes and floods. This is by no means accidental. Tang Dynasty's Preface to Shiqiao said, "People don't know why it's amazing." This evaluation is almost the same as that of engineering scholars in the twentieth century, and it is highly skilled, which can be seen here. In a large number of historical facts, the technical achievements of ancient stone arch bridge "saving materials, skillful structure and high strength" are summarized, which is the consistent goal pursued by bridges and any buildings at home and abroad. At the beginning of the 6th century, China's skillful craftsmen displayed their intelligence and made bold innovations, and their brilliant achievements were worthy of pride.
Thirdly, bridging the bridge across the water, the beauty of artistic conception, the beauty of carving and decoration, and the diversity of styles are also the national traditions that embody China's aesthetic standards. No matter the size of the building, the technology should be improved, just like painting, there can be no failure. Since the prevalence of grotto statues, ancient masons have had a set of superb skills and a certain level of artistic design. The railings in Zhao Zhouqiao and the stone lions in Lugou Bridge are both famous for their artistic treasures, which is also a precious artistic tradition of Chinese stone arch bridges and has a far-reaching influence on the decoration of modern stone arch bridges.
The stone arch bridge in China has made some achievements in ancient times, and it still has development prospects today. What used to be useful is still working today. Therefore, it is a precious heritage, showing the industriousness, courage and outstanding talents of the working people in our country. We will certainly make greater achievements in the cause of modern bridges.
Arch bridge is one of the basic systems of bridges, with a long history and beautiful appearance. Famous bridges in ancient and modern China and abroad occupy an important position in bridge construction. It is suitable for large, medium and small span roads or railway bridges, especially for crossing canyons. Because of its beautiful shape, it is also often used in bridge construction in cities and scenic spots.
/kloc-since the middle of the 0/9th century, with the appearance of steel and concrete building materials, stone arch bridges have been gradually replaced by steel arches and reinforced concrete arch bridges. The arch bridge structure develops to light structure, gradually breaking the traditional through stone arch bridge and creating a new arch bridge. The arch ring of the arch bridge has developed into a separated rib arch, and the bridge deck has developed into a new plate beam structure, which is supported on the arch rib by columns (through type) or suspended under the arch rib by suspenders (through type). When restricted by terrain or bridge construction height, it can also be made into a half-through arch bridge. Arch bridges can be single-span or multi-span.
Box-ribbed half-through arch bridge
Classification:
1. According to the stress of arch ring: thrust arch bridge and non-thrust arch bridge.
2. According to the material of arch ring (rib) structure, it can be divided into stone arch bridge, steel arch bridge, concrete arch bridge and reinforced concrete arch bridge.
Single hole hollow stone arch bridge
Reinforced concrete inclined tied arch bridge
3. According to the static diagram of arch ring (rib) structure, it can be divided into hingeless arch, double hinged arch and three hinged arch. The first two are statically indeterminate structures, and the latter is statically indeterminate structures. Both ends of the arch ring of the hinged arch are fixed on the abutment (pier), so the structure has the greatest rigidity and less deformation, which is more economical than the hinged arch. However, factors such as abutment displacement, temperature change or concrete shrinkage will adversely affect the stress of arch, so the construction of articulated arch bridge needs a solid foundation. The double hinged arch is provided with rotatable hinge supports at both ends of the arch ring, and the hinge supports allow the two ends of the arch ring to rotate a little. Although the structure is not as rigid as hinged arch, it can weaken the adverse effects of abutment displacement and other factors. Three-hinged arch is to add another hinge to the double-hinged arch, which makes the structural stiffness worse, but it can avoid the adverse effects of various factors on the stress of the arch ring. Awesome! Zhao Zhouqiao, also known as Anji Bridge and Dashi Arch Bridge, is located on Qingshui River, five miles south of Zhao County, Hebei Province. It is not only the first stone arch bridge in China, but also the first stone arch bridge in the world today. Literati in the Tang Dynasty praised the bridge "at the beginning of the month, Yun Qi, Changhong drinks".
This bridge was built in the Sui Dynasty from 605 to 6 18. It was built by an ordinary stonemason, Li Chun, with a history of 1350 years. In the long years, despite numerous floods, wind and rain, ice and snow erosion and eight earthquakes, it stood on the Qingshui River unscathed.
The Zhao Zhouqiao designed by Li Chun is 50.82 meters long, 9.60 meters wide, with a clear span of 37.37 meters and an arch height of 7.23 meters. He considered that in order to make the slope of the bridge deck small, the height-span ratio of the bridge 1: 5 is convenient for pedestrians and vehicles to pass. The vault is so high that it is easy to sail under the bridge. He also made two small arches on the shoulders of the big arch, which made the whole bridge look particularly balanced and symmetrical, which not only facilitated flood discharge in rainy season, but also saved building materials. Its structure is magnificent, gorgeous and reasonable, which is imitated by later generations. The bridge deck designed by Li Chun is straight and divided into three strands, with chariots and horses in the middle and pedestrians on both sides, which can not only maintain order, but also prevent traffic accidents. It can be seen that 1300 years ago, under the condition of very backward technology, an ordinary stonemason Li Chun had such superb technology, which is really commendable.
Li Chun's stone and stone masonry skills are different. He used rectangular stones, each weighing about one ton. More than 65,438+0,350 years ago in the Sui Dynasty, it was difficult for Li Chun to transport such a heavy stone without cranes and cranes. This fully shows the great wisdom of our working people. It can be seen how much effort and cost Li Chun has paid!
Li Chun led other craftsmen to carve fine twill on each side of the stone, so that the stone was interlocked and fixed. The whole bridge consists of 28 independent stone arches side by side. He thought that this would allow each stone arch ring to bear its own load independently and facilitate maintenance. In order to strengthen the connection of the arch ring, he used nine iron beams to penetrate the arch back, and then embedded waist iron between the arch stones, so that the bridge was "ingenious and used by the world."
Finally, Li Chun organized craftsmen to carve many exquisite classical carving arts on the stone railings on both sides of the bridge deck. Exquisite design, vigorous and powerful knife cutting, changeable carving spirit, and all kinds of birds and animals are lifelike, which can be called a masterpiece of sculpture art in Sui and Tang Dynasties. This new type of bridge with upper arch and lower arch and "open shoulder arch", this layout and this huge span form such a beautiful shape, which is the first in Li Chun's world. In Europe, the Sylar Bridge on the Teke River appeared in the14th century, but it was more than 700 years later than Zhao Zhouqiao in China, and it was already destroyed by floods. Therefore, the Zhao Zhouqiao built by Li Chunzao is the only one with the longest survival time in the history of bridge construction in the world, which occupies an important position and is of great value in the world. This is the pride and pride of the people of China.
This Zhao Zhouqiao, with a long history, unique structure, beautiful appearance and the first place in the world, embodies Li Chun's sweat and hard work. Li Chun became the first bridge expert in the architectural history of China and even the world.
However, there is no more record about Li Chun's life story. Even after the Sui Dynasty, people in the Tang Dynasty only recorded it in several languages, such as "The person who made the strange Zhao Zhouqiao was Li Chun, a craftsman of the Sui Dynasty". Zhang Shizhen, the secretary after Kaiyuan 103 (AD 726) was built in Zhao Zhouqiao 100 in the Tang Dynasty, briefly mentioned in the inscription of Anji Bridge: "The stone bridge of Qingshuihe in Zhaozhou, the trace of Li Chun, a craftsman of Sui Dynasty, is also strange, and people don't know what he did." This shows that in feudal society, I don't know how many inventions and creations of working people were buried.
It is particularly worth mentioning that Zhao Zhouqiao has a very solid foundation. Since 1350, the settlement of bridge foundations on both sides is only 5 cm, which shows that the site selection of Li Chunqiao is scientific and reasonable. The foundation of Zhao Zhouqiao Bridge is built on the white coarse sand layer of Qingshui River bed. There is neither piling nor other stones. The abutment only uses five layers of stones. The bridge foundation is firm and the structure is simple. Before 1350 years ago, Li Chun dared to bear all the weight of the bridge with such natural foundation, which showed that Li Chun had a profound understanding of engineering, mechanics, architecture, hydrology and geology. Li Chun has so much scientific knowledge, which is undoubtedly obtained and accumulated from his labor practice.
Zhao Zhouqiao showed the great wisdom of the ancient working people in China, and Li Chun's name will go down in history forever.
"Yixiantian" Bridge, the longest railway stone arch bridge.
On both sides of the Dadu River in Sichuan, there is a big crack called Laochanggou, which is divided into several miles by an ancient Liangshan. The two sides of the ditch are parallel to each other, and the mountain wall is steep and straight into the sky. This ditch is more than 200 meters deep and only 50 meters wide. The clouds in the ditch are floating around, looking up at the sky from the bottom of the ditch, hanging in the air like a blue rope, which is called "a scene on the horizon" When chengdu-kunming railway 1964 was built, bridge builders built a railway stone arch bridge with the largest span in China.
During the period of 1965, when compiling the track-laying schedule of chengdu-kunming railway, Southwest Railway Construction Engineering Headquarters found that it would take more than one year to complete the bridge if precast beam structures were used intensively, so it was decided to change some beam bridges into stone arch bridges to shorten the construction period, reduce the long-distance transportation of cement and achieve the purpose of opening to traffic in advance. The bridge was changed from a simply supported beam bridge to a stone arch bridge.
Shi Tian Arch Bridge is located in the northern section of Chengdu-Kunming Railway, between Guancunba and Changheba, and crosses Laochanggou, a tributary of Dadu River. Geology of the bridge site, the bottom of the ditch is alluvial boulder soil, pebble soil, gravel soil and silty coarse sand, with a total thickness of more than 25m; The trench walls on both sides are Sinian limestone, where gentle folds are formed locally, joints are developed and the rocks are hard.
With a span of 54 meters, the bridge is the largest hollow railway stone arch bridge in China, with a total length of 63. 14 meters and a traditional architectural structure. The total masonry volume of the whole bridge is more than l600 cubic meters, and there are 4930 arch stones. The arch stone is made of granite gneiss collected along the Dadu River from Wu Si River to Maotouma, which blends with the nearby rocks and is particularly spectacular.
Stone arch bridge is located on the longitudinal slope of 3% o straight line, and the stress of main arch ring is calculated according to the principle of fixed-end hinged arch. The main arch span is 54m, the arch height is 13.5m, the arch width is 4m, the vault thickness is 1.6m, the arch foot thickness is 2.8 15m, and the arch axis is an inverted catenary. The arch structure is a small catenary arch with equal cross-section, with three holes at both ends, a span of 5 meters, a rise-span ratio of 1: 2 and an arch thickness of 0.5 meters, which makes the appearance more harmonious. One end of the outer small arch extends into the tunnel and is supported on the rock foundation, and the other end is supported on the pier of the main arch ring. In order to separate the structure on the arch from the rocks on both sides of the river and play the role of expansion joint, the middle span adopts three hinged arches, and the inner and outer spans adopt non-hinged arches. The main arch ring was laid in July of 1966, and completed in June of the same year 10, which lasted 99 days and the construction speed was relatively fast. The whole bridge takes 456 15 working days, with an average of 722.4 working days per meter.
During the construction, workers used simple equipment to dig plank roads, climb cliffs, bury earthworms, set up cables and skillfully install steel arches. In the process of construction and installation for more than three months, they have achieved high standards and strict requirements, carefully constructed and ensured the quality of the project. After decades of operation, all parts of the stone arch bridge are intact and the structural performance is good. The construction experience of "Yixiantian" stone arch bridge shows that long-span stone arch bridge should be built according to local conditions, saving steel and cement, avoiding deep foundation and high pier when deep valley and topographic and geological conditions permit. The stone arch bridge is durable, does not need regular overhaul operation, and has low maintenance cost. Building small and medium-span railway bridges in mountainous areas can give full play to the advantages and functions of stone arch bridges.
The largest span reinforced concrete arch bridge of China Railway-the Seventh Yongding River Bridge-the Nanjing Yangtze River Bridge is a new milestone in China's bridge construction.
Stone arch bridges use huge stones to pass water, both north and south, accounting for the majority of the bridges. In the south, the river is narrow, and ships sail in the river. The transportation on the bridge mainly depends on shoulders, so the arch span does not need to be too large, and the arch back is extremely high. In the north, on the other hand, the river is wide and shallow, and there are often no boats in the river. Bridges are mainly transported by chariots and horses, and the arch back does not need to be too high, and the deck is flat. Thus, the style differences between the south arch bridge and the north arch bridge are formed.
The oldest existing bridge in China is a single-span stone arch bridge, namely Anji Bridge in Zhao County, Hebei Province, which was built in the Sui Dynasty (605 ~ 6 17).
The river under Anji Bridge is usually only a trickle, which is not navigable, and the river surface is wide. Therefore, bridge opening should have a considerable span, not too high, and the bridge deck should be flat without steps, which can represent the style of the northern stone arch bridge. Anji Bridge is the first large-span arch bridge in the world, with an arch span of 37.47 meters, a rise less than one-fifth of the arch span, and a bridge top width of 8.5 1 meter. There are 28 parallel arches in the longitudinal direction of the whole bridge (that is, along the span direction), each arch can be built one by one, and the formwork can be reused, which is convenient for construction. In order to strengthen the lateral connection between bills and prevent the bills from tipping outward, iron sheets and cross-stones are used to strengthen the connection between bills, and the width of the two bridge feet is 5 1 cm to 74 cm wider than the width of the bridge top, so that the bills are naturally squeezed inward. Every time it rains heavily in this river, the water will cross. In order to increase the discharge surface during flood, two holes are opened on each shoulder between the bridge deck and the bridge deck, which is called open shoulder arch. This practice, initiated by China, also has the functions of reducing self-respect, reducing engineering quantity and enriching modeling.
The bridge deck is in a gentle convex arc. At the bridge head, this arc is slightly concave, and the curve of the whole bridge is very beautiful and stretched. The arc radius of the bridge deck is larger, and the bridge connection radius is smaller, one is loose and the other is loose, forming a strong support contrast relationship. The arch back elevation of the four small open-shouldered arches and the bridge deck arch gradually moves down from the middle to the outside, and their trajectory connection lines are bridge deck arcs. The contrast between the big archway and the small archway shows the real scale of the big archway, and the practices of each archway are consistent, emphasizing unity. The permeability of the small arch makes the whole bridge look ethereal and light, and the load is light. Anji Bridge is a high combination of truth, goodness and beauty. The artistic level it has achieved has attracted constant admiration from future generations. We compare it to Hong Fei, Black Dragon, Yuhuan and Crescent, and appreciate its stretch and lightness.
Compared with other types of buildings, the practical requirements of bridges are more clear and simple, and the technology is stronger, but even so, bridges are of great significance for beautifying life and decorating the country, and are also the object of architectural art's attention. In some cases, the combination of bridge and building or environment may also bring some deep spiritual and cultural significance. For example, the five stone arch bridges in front of Tiananmen Square in the Forbidden City in Beijing face five openings, with the largest one in the middle and the other four smaller in turn. Together with Tiananmen Square and the surrounding environment such as huabiao and stone chambers, they form the entrance to the palace, which strengthens the momentum of this royal building. There is also a small bridge in front of the temple to mark the importance of architecture. Bridges in gardens require closer integration with the landscape, which requires higher aesthetic feeling of modeling. Together with other garden landscapes, they create an elegant atmosphere. These bridges are not only of simple and practical significance. They are not only a traffic facility, but also a landscape sketch. Their beauty, in addition to technical beauty, is more narrow artistic beauty.