Chinese Bridge Technology active on the international stage
No matter what type of bridge type, such as cable-stayed bridge, suspension bridge, arch bridge, and so on, in the top ten bridges in the world, close to or more than half of the bridges are in China. From the beginning of the last century in 80s, after decades of development, China's bridge technology has made great progress, reflected the span of the leap to some extent is the bridge of technological progress specifically, we in the new materials, new structures, new equipment, new technology has made great progress in 4 aspects.
On the new material, the strength and performance of the bridge steel has been developing, from 16 manganese to Q370qE, Q420qE, until Q500qE. The strength of the cable-stayed cable also develops to 2000 MPa level.
The new structure, Wuhan Tianxingzhou Yangtze River bridge's first three cable planes and three main truss cable-stayed bridge, composite structure using steel deck and concrete bridge deck, Shanghai Yangtze River bridge steel truss composite structure...... In addition to the porous continuous span suspension bridge and cable-stayed bridge, China is at the forefront of the world.
The construction technology and the method of engineering are also progressing. Wuhan Tianxingzhou Yangtze River bridge first anchor pier location, change of double wall steel cofferdam with water lifting load, steel truss can have a large segment hoisting, Fujian and the Pingtan Strait Bridge rail will use the whole hole hoisting, Shanghai Yangtze River bridge shipyard by floating caisson overall manufacturing technology and positioning technology of large diameter steel piles and all of these technologies are leading in the world.
Some achievements have been made in the research and development of new equipment. For example, Wuhan Tianxingzhou Yangtze River bridge developed KTY-4000 type drilling rig, the maximum pore diameter of 4 meters, while the Pingtan Strait rail bridge is developed KTY-5000 type drilling rig, a hole up to 5 meters. To some special large-scale bridge construction equipment, such as large vibration hammer, large tonnage crane, have been or will be put into use.
Nevertheless, China is still a big bridge country at present. There is still a gap between the bridge and powerful country. It is mainly behind the R & D field, including the development of some special equipment, which is closely related to the level of industrialization in China.
A comprehensive consideration of the whole process of building a century project
Today, the design and service life of the super large bridge will exceed 100 years, and the design and service life of the Hong Kong Zhuhai Macao Bridge will be more than 120 years. Even some academician experts have proposed that the service life of a special bridge should be 200 years.
To build a hundred years of service life, we must first consider the whole life cycle of the bridge from the perspective of design, including planning, design, construction, operation and maintenance and demolition. The design of the bridge should be considered from the safety, durability, beauty and other aspects, the use function of bridge and bridge structure, the structural stress can meet the design life, such as fatigue and structure, anti-corrosion durability on whether there is a problem, which is to be considered when designing. Besides, for the cross sea bridge, the corrosion problem of steel piles should be considered. The ordinary steel structure will rust very badly in the sea, so we must adopt some protective measures, such as painting protection, as well as marine concrete.
Next is the construction quality to meet the requirements, the material is not qualified, the process is not in place will affect the life of the bridge. For example, the concrete mix ratio is not reasonable, the vibration is not in place, maintenance is not in place, will lead to concrete voids and pits cracks, a long time, will be corroded.
Finally, the durability of the bridge is considered from the angle of management and maintenance, and the vehicle is managed and overloaded in the operation and maintenance. Intelligent health monitoring systems will be introduced to some large bridges, especially major bridges. In the busy shipping traffic zone, is to set the anti-collision facilities in the pier, on the icy river, set ice structure.
The bridge in China can completely "go out"
At present, the peak of bridge construction has long been in the past. China is still at its peak, but such a rush hour will not continue. Once the investment is reduced, it will cause a lot of labor and equipment to be idle. Therefore, it is a general trend for China's bridge building industry to go abroad. Along with the high-speed rail going out of the country, the bridge area has enough capabilities and advantages in design, technology, materials, machinery and equipment to go all the way to the world.
We have our advantage, the question is where to go. Although Europe, America, Japan and other countries have passed the construction peak, the technology, equipment and scientific research strength still lead the international market, and we are very difficult to enter.
Our direction is to follow the national "The Belt and Road" to go outside, such as Burma, Bangladesh and Pakistan, including some parts of Southeast Asia and africa. In these places, we still have some advantages. However, after we go out, we must adapt ourselves to the international general project management mode, as well as the mastery and application of rules and regulations, so that workers should be localized so as to reduce costs.
It can be said that we have the ability to build bridges under any harsh geological conditions. The performance of China's transportation construction enterprises has far exceeded that of any country's construction enterprises.
The reason why China's high speed rail can "go out" is because China has built various railway lines from south to north, from east to west. Have a cold northeast permafrost region, regional railway, Xinjiang, Tibet plateau railway, Ningxia Gobi railway in the desert, a tropical rainforest in Hainan on the railway, those countries "The Belt and Road" along the way, you can always find a similar geological and meteorological conditions and the corresponding in China. Of course, there are independent trains and so on.
The railway has this condition, and the bridge is more like this. In any of these railway lines with different geological and meteorological conditions, there are also a large number of bridge projects. Therefore, in any place to build a bridge, our country's technology is mature, and the team and equipment are mature.
As for the proportion of bridges, it depends on where it is built. Like the boundless plain in the plain area, the roadbed must be less than the bridge. While in Sichuan, Yunnan, Guizhou and other areas, the proportion of bridge and tunnel is very high. Just sign the old railway bridge, accounting for 60%. In the mountains, and is often more than 50%. In addition, in order to reduce the occupation of the land and protect the ecological environment, it is often used to bridge the road through some weak geological sections, which also makes the proportion of the bridge greatly improved.
In this round of high speed rail construction, we have built a large number of influential bridges in the world. Including access to national science and Technology Progress Award and the George Richardson prize of Wuhan Tianxingzhou Yangtze River bridge, and won the award of outstanding international bridge and structure engineering co National Prize for science and technology of Nanjing Dashengguan Yangtze River bridge, is building the world's largest rail suspension bridge with span two - five Jiangsu Fengshan rail bridge and the world's largest span highway railway cable stayed bridge, Shanghai Yangtze River bridge, the main span is 1092 meters...... They will become the bright cards of Chinese bridges, showing the construction level of Chinese bridges to the world, and play a crucial role in the process of "going global".
