High scores for papers, about Hangzhou Bay Bridge ... ...
The total length of Hangzhou Bay Cross-sea Bridge is 36 kilometers, including 35.7 kilometers. It is a two-way six-lane expressway with a design speed of 1km kilometers per hour. The total investment is about 1.7 billion yuan, and the design service life is more than 1 years. The bridge has two navigation holes in the north and south. The North Navigation Span Bridge is a steel box girder cable-stayed bridge with twin towers and double cable planes with a main span of 448m, with a navigation standard of 35, tons. Nantong Hangkong Bridge is a steel box girder cable-stayed bridge with single tower and single cable plane, with a navigation standard of 3, tons. The connecting line between the two sides of the bridge has a total length of 84.4 kilometers and an investment of 5.21 billion yuan. Among them, the northern connecting line is 29.1 kilometers, with an investment of 1.78 billion yuan; The south bank is 55.3 kilometers long with an investment of 3.43 billion yuan. The total investment of the bridge and the cross-strait connecting line is about 16 billion yuan. The construction period is about five years.
Hangzhou Bay Cross-sea Bridge is the longest cross-sea bridge rebuilt in the world at present. The bridge is located in the Yangtze River Delta, which is the most dynamic and economically developed area in China. The project started construction in an all-round way at the end of 23 and is expected to be completed by the end of 28 and opened to traffic in 29.
the concept of landscape design was introduced into the design of the bridge for the first time. With the help of the aesthetic concept of "Long Bridge Lying on the Wave" in Su Causeway of West Lake, landscape designers have determined the general layout principle of the bridge, taking into account the hydrological environment characteristics of Hangzhou Bay and the psychological factors of drivers and passengers when driving. The plane of the whole bridge is S-shaped curve, and the overall line shape is beautiful and lively. Viewed from the side, the navigation hole bridges in the North-South Waterway are each arched, with an undulating elevation shape. < P > The construction of the bridge is conducive to actively connecting with Shanghai, expanding opening up, promoting cooperation and exchanges in the Yangtze River Delta region, improving the opening level of Zhejiang Province, especially Ningbo and Jiaxing, and enhancing its comprehensive strength and international competitiveness; It is conducive to improving the layout of regional highway network and national trunk lines in the Yangtze River Delta, and alleviating the pressure of traffic in Shanghai, Hangzhou, Ningbo and Expressway. It is conducive to changing the situation of Ningbo's traffic terminal, thus becoming a transportation hub and implementing the regional development strategy around Hangzhou Bay; It is conducive to promoting the development of tourism in Jiangsu, Zhejiang and Shanghai.
Hangzhou Bay Bridge is a convenient passage for Shenhai Line, the national trunk line, to cross Hangzhou Bay, and it is a part of Hangzhou Bay Ring Road (G92) of the national expressway network. The bridge starts from Zhengjiadai, Haiyan, Jiaxing City in the north, crosses the wide sea area of Hangzhou Bay and ends at Shuilu Bay, Cixi, Ningbo City, with a total length of 35.5km. After the completion of the bridge, the land distance between Ningbo and Shanghai will be shortened by more than 12 kilometers, thus greatly alleviating the pressure of the already crowded Shanghai-Hangzhou-Ningbo Expressway and forming a two-hour traffic circle between Jiangsu, Zhejiang and Shanghai with Shanghai as the center.
engineering features 1. engineering environment features
the weather in Hangzhou bay is complex and changeable, and typhoons, tornadoes, thunderstorms and sudden small-scale disastrous weather occur from time to time. The natural conditions of Hangzhou Bay have the following characteristics:
(1) The sea area is vast, with many typhoons, large tidal range and rapid flow, which has typical maritime climate characteristics and few effective working days;
(2) The thick soft soil layer and deep bearing layer bring a series of problems to the design and construction of offshore foundation;
(3) The south beach is long, and the construction conditions are complicated, so it is difficult to meet the construction period requirements by using conventional design schemes and construction methods;
(4) the environment is seriously corrosive;
(5) shallow gas is enriched in many areas of south beach, which endangers the construction safety.
2. Difficulties in project construction
(1) The project scale is large and the offshore engineering quantity is large. The total length of the bridge project is 36 kilometers, and the length of the offshore section is 32 kilometers. The whole bridge has a total of 2.45 million cubic meters of concrete, 82, tons of various steels, 5,513 steel pipe piles, 3,55 bored piles, 1,272 caps and 1,428 piers, and the project scale is huge.
(2) the natural environment is harsh. Large tidal range, rapid flow velocity, chaotic flow direction, high waves, deep scour, thick soft stratum and rich shallow gas in some sections. Among them, the wet and dry alternate in the 1-kilometer beach area on the south bank, and most of the offshore projects are offshore operations, with poor construction conditions. Affected by hydrology and meteorology, the effective working days are few. According to the statistics of on-site construction, the annual effective days of offshore construction operations are less than 18 days, and the tidal flat area is about 25 days.
(3) It is very difficult to make the overall design scheme. The design requirements are new, in which the approach bridge in the water area (18.27 km) and the approach bridge in the south bank tidal flat area (1.1 km) are the key points of the whole project; The problem of structural corrosion protection is very prominent, and there is no specification to follow; During the operation of the bridge, the driving environment on the bridge deck is affected by unfavorable factors such as strong wind, dense fog, heavy rain and driver's visual fatigue, so it is the key to ensure the driving safety on the bridge deck to adopt reasonable and effective design countermeasures. The design scheme involves the application of new materials, new processes and new technologies and the development of a number of large-scale special equipment.
in terms of construction technology, it faces the challenges of many key construction technologies, such as the overall prefabrication, transportation and erection of large-tonnage box girder in high pier area of offshore rapids, long-distance beam transportation and erection of large-tonnage box girder in wide beach area, design of super-long spiral steel pipe pile, anti-corrosion and pile sinking construction, etc. In terms of survey control, the structural survey deformation caused by the over-long bridge length and the earth's curved surface effect is very prominent. Restricted by the marine environment, traditional survey methods can no longer meet the requirements of construction accuracy and progress. How to realize rapid and efficient survey construction with the help of GPS technology is a core technical problem that restricts the construction period of the whole bridge.
(4) The construction goal is demanding, and the construction organization and operation management are difficult. The large-scale bridge project has attracted worldwide attention. At the beginning of construction, Ningbo Municipal Party Committee and Municipal Government clearly proposed that the bridge project should be implemented according to the standard of "three first-class goals". Facing the complex construction environment and challenging projects, it is a great challenge for the headquarters to organize and manage the bridge project well. Because of the large number of construction sites and long battle lines, there are synchronous and cross-working procedures, which makes it difficult to organize the construction and control the quality, progress, safety and funds of the project. Under the meteorological and hydrological conditions such as typhoon, strong wind, spring tide, huge waves, rapids, heavy rain, fog and lightning, how to take effective engineering control and operation management measures is a new topic that needs to be faced in engineering management.
The 36km length of the bridge highlights the bridge, which makes it surpass world famous bridge such as Chesapeake Bay Bridge and Bahrain Road Embankment Bridge in the United States and become the longest sea-crossing bridge built or under construction in the world.
according to the preliminary approval, the bridge needs 769, tons of steel, 1.291 million tons of cement, 11,6 tons of petroleum asphalt, 19,1 cubic meters of wood, 2.4 million cubic meters of concrete and more than 7, piles of various types, making it the largest bridge in China. The 5-meter * 16-meter box girder in the south beach is prefabricated by whole hole, and the girder is transported on the girder by large flat car, which has set a new record for heavy girder transportation at home and abroad.
The 7m× 16m box beam of the approach bridge in the underwater area adopts the integrated scheme of whole hole system, transportation and erection, and the single beam weighs 2,18 tons, ranking first in China. The diameter of steel pipe piles driven into the approach bridge in the underwater area is 1.5-1.6 meters, and the pile length is about 8 meters, with a total number of more than 4,. The scale of steel pipe piles is the first in the history of bridge construction in China.
the concept of landscape design was introduced into the design of the bridge for the first time. With the help of the aesthetic concept of "Long Bridge Lying on the Wave" in Su Causeway of West Lake, landscape designers have determined the general layout principle of the bridge, taking into account the hydrological environment characteristics of Hangzhou Bay and the psychological factors of drivers and passengers when driving. The plane of the whole bridge is S-shaped curve, and the overall line shape is beautiful and lively. Viewed from the side, the navigation hole bridge of the North-South Waterway has an arch shape, which has an undulating elevation shape.
1.7 kilometers south of Nanhang Road, about 14 kilometers from the south bank, there is a platform in the sea with an area of 12, square meters. During the construction period, the platform will be used as a living base for offshore operators and a platform for maritime rescue, measurement, communication and maritime monitoring. After the completion of the bridge, this platform in the sea is a rescue platform for transportation services in the sea, and it is also an excellent sightseeing platform for tourism and leisure.
Hangzhou Bay is located in the Yangtze River Delta, which is the most dynamic and economically developed area in China. The construction of Hangzhou Bay Bridge is of far-reaching and strategic significance to the economic and social development of the whole region.
1. directly promote the economic and social development of Ningbo and Jiaxing, promote the development of surrounding areas such as Hangzhou, Shaoxing, Taizhou, Zhoushan and Wenzhou, and have a positive impact on the overall development of the whole province and even the southern wing of the Yangtze River Delta. According to statistics, the GDP of Hangzhou, Ningbo, Wenzhou, Shaoxing and Taizhou accounts for more than 7% of the whole province. The project construction will make the development of these areas even more powerful, inject new vitality into the further development of regional economy and society, and play a greater role in improving the overall comprehensive strength of the whole province. The bridge project has not yet started in an all-round way, and Cixi City, Yuyao City and Haiyan County of Jiaxing on both sides of Hangzhou Bay have been surging with "bridge economy". On the basis of scientific planning of the new area, the first phase of development has shown a vigorous scene, and investors have settled here one after another.
2. Take the initiative to open wider to Shanghai, promote cooperation and exchanges in the Yangtze River Delta, and further enhance the comprehensive competitiveness and international competitiveness of our province. As the largest economic center city in China, Shanghai is an important platform for China's internationalization. In the new century and new stage, Ningbo should build a modern international port city and achieve great economic development and leap forward. It is necessary to integrate with Shanghai, integrate into the Yangtze River Delta and move towards internationalization. The construction of the bridge will greatly shorten the time and space distance between the southeast coast of Zhejiang and Shanghai, so that our province can be integrated into the international metropolis economic circle in a larger scope, at a higher level and with superior geographical advantages. This has a far-reaching positive effect on radiating the vast hinterland of our province, optimizing and upgrading the industrial structure, improving the investment and development environment, attracting foreign investment and improving our comprehensive competitiveness. The construction of Hangzhou Bay Bridge will create more favorable conditions for optimizing the development environment, further attracting and utilizing foreign capital.
3. It is conducive to promoting the urbanization development strategy. The construction of the bridge will further strengthen the connection between Jiaxing, Ningbo, Shaoxing and Taizhou, and promote the formation of Hangzhou Bay urban continuous belt and coastal opening-up sector in our province, thus upgrading this area to the most important part of an internationally competitive metropolitan group with Shanghai as the leader. At the same time, the construction of the bridge will also have a far-reaching impact on the urbanization development of surrounding counties and cities. Cixi, Haiyan and other places aim at this once-in-a-lifetime strategic opportunity and have scientific planning ideas to attract population and industry to gather and promote the rise of new districts and new cities.
4. As the first sea-crossing bridge in China's coastal corridor, it broke through the bottleneck of Hangzhou Bay, optimized the road network layout of national trunk lines, changed the traffic terminal situation of Ningbo, and was conducive to the implementation of the regional development strategic network around Hangzhou Bay, greatly enhancing the competitiveness of Ningbo, an economic center city with great development potential. The construction of the bridge is also conducive to supporting the construction of Shanghai International Shipping Center, promoting the integrated development and utilization of Ningbo and Zhoushan deep-water port resources, promoting the development of tourism and national defense construction, and alleviating the pressure of highway traffic in Hangzhou transit (Shanghai-Hangzhou-Ningbo Expressway).