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preface
3,000 years is a snap of the fingers for a people, but for a bridge, it is equivalent to eternity.
When American experts arrogantly claim that it will take China 3,000 years to build the bridge they will complete in 300 years, no one would have imagined that just three years later, Chinese would have shattered this seemingly absurd prophecy with actions.
This seemingly fantastical "impossible mission" was so easy and simple in the face of the spirit of overcoming difficulties in Chinese.
What kind of bridge have we built that has stunned the world?
Beipanjiang Bridge: The world's highest bridge, a masterpiece of China's intelligent manufacturing
The Beipanjiang Bridge spans Qujing City in Yunnan Province and Liupanshui City in Guizhou Province, connecting the two ends of the Hangzhou-Rui Expressway.
Construction began in 2013 and took three years to complete, as another world-record-breaking feat in the mainland.
The bridge is located in a deep mountain and old forest at the junction of Qujing and Liupanshui with an altitude of more than 2,000 meters, the terrain is steep and complex, and the Beipanjiang Grand Canyon spanning by the bridge is more than 600 meters deep, forming a bottomless abyss.
Both sides of the canyon are typical karst landforms, and the cave structure is developed, and it is undoubtedly more difficult to build bridges in this geological environment.
When the relevant departments of the mainland decided to build this bridge connecting the two places, many foreign professional bridge design companies sent personnel to conduct on-site investigations, but without exception they all said that they could not build bridges here.
Some American experts even said sarcastically that if the United States builds such a bridge, 300 years may not be enough, and it will take 3,000 years for China to build it.
However, the mainland government has not flinched from these external criticisms, and China pays attention to the "invincible road", opening roads in every mountain and building bridges when encountering water, which is difficult to accumulate Chinese engineers and technicians with rich practical experience.
In order to determine the best bridge site, the relevant departments organized technicians to conduct a year-long survey of the surrounding terrain, and after careful demonstration, it was finally decided to build a bridge on a steep cliff about 600 meters from the canyon.
Such a large height difference is equivalent to the height of more than 200 buildings, if Shanghai's landmark Oriental Pearl is erected here, its spire will be more than 100 meters higher than the bridge, and the piers need to be built on this cliff, which shows the difficulty of the project.
In order to cope with the karst cave geology, Chinese engineers and technicians have developed a building material called "smart concrete".
It can automatically fill a variety of narrow spaces, enrich and strengthen the cave structure, greatly improve the construction quality and safety, and creatively add auxiliary piers in the position of piers with more caves to enhance the stability of the bridge structure.
After the piers are opened, how to erect the bridge deck and cables between the steep cliffs on both sides is also a big problem.
The technicians repeatedly demonstrated and adopted the side span jacking construction method: using the shore or pier as the support point, the assembled bridge section was gradually pushed out from one side, and finally hoisted onto the bridge tower.
The 160-ton steel truss is prefabricated on the ground and hoisted into the air 200 meters by a large crane for docking. In order to ensure the accuracy of the interface, the error of the bolt during docking should not exceed 5 mm.
In order to resist strong wind and cold, engineers specially selected high-strength steel wire with a strength of more than 1800 MPa to make a cable-stayed cable with a diameter of only 15 mm and a total of 224 cables, which became the stable "meridian" of the bridge.
After arduous efforts, the Beipanjiang Bridge was finally completed and opened to traffic in 2016, with a total length of more than 1,300 meters, a vertical height of 565 meters from the bridge deck to the valley floor, 4 lanes in both directions, and a design service life of up to 100 years.
The height of the main piers on the east and west sides reaches 269 meters and 247 meters respectively, and its main span of 720 meters ranks second in the world among bridges of its kind.
This Beipanjiang Bridge, which has broken many world records, fully demonstrates the spirit of Chinese engineers and technicians bravely climbing the peak and the true Chinese color of tenacious struggle.
Just as the Chinese nation has always advocated the spirit of "paradise", Chinese has the courage to forge ahead and the wisdom to create miracles when the mountains and rivers are exhausted, and the doubts of the outside world have never shaken the pace of the Chinese nation.
The Beipanjiang Bridge is a vivid interpretation of this spirit, and will also inspire more latecomers to brave hardships and dangers and innovate.
Comparison of Sino-US bridges: the construction of the Beipanjiang River Bridge in Yunnan
The construction of Beipanjiang Bridge is of epoch-making significance to the development of bridge engineering in China, due to its location in a canyon and complex and changeable terrain, the site selection, design and construction of the bridge are facing great difficulties and challenges.
In order to ensure that the pier can be firmly and stable, the designer finally selected the position of the pier on the mountainside at an altitude of more than 560 meters after repeated comparison and demonstration.
At the time, this was undoubtedly the "highest record" in the world, and working at height placed extremely high demands on concrete conveying and pier foundation construction.
Chinese engineers and technicians actively carry out technology research and development, and have invented a smart concrete that can be automatically filled according to the mold, thus ensuring the quality of concrete and construction progress.
Then there is the problem of lifting the main bridge and main tower structure, and ordinary high-altitude lifting equipment cannot reach a working height of 560 meters, so the project department adopted an innovative scheme of lateral movement from the mountains on both sides.
However, due to the high altitude and strong wind, ordinary lifting operations are too risky, and Chinese engineers and technicians have developed a set of sensor monitoring systems.
By collecting various real-time data and feeding the information back to the computer terminal, the lifting process is visualized and accurate, which greatly reduces the risk of error and ensures the safety of construction personnel.
The more severe challenge lies in the psychological pressure of the construction personnel, working at an altitude of 560 meters, even if there are safety measures, it is inevitable to have a fear of heights.
But for the sake of this bridge and the development of the region, the construction personnel braved hardships and dangers, overcame fear, persevered in completing the aerial work, and their dedication also became an important pillar of the construction of the Beipanjiang Bridge.
China also faced skepticism from American experts who asserted that it would take at least 3,000 years to build a bridge on such terrain.
But the Beipanjiang Bridge was built in only 3 years, becoming a miracle in the history of world engineering and also slapped the narrow remarks of American experts.
In contrast, the Golden Gate Bridge in San Francisco, USA, also adopts a suspension bridge structure, but its difficulty and innovation are far less difficult and innovative than the Beipanjiang Bridge.
The Golden Gate Bridge is only built across the sea, with an altitude of only 340 meters, and faces superior terrain and climatic conditions. The design concept and technical route of the two bridges are significantly different.
The completion of the Beipanjiang Bridge fully demonstrates the courage and creativity of Chinese engineers, enriches the history of bridge engineering construction in the world, and cannot simply be classified as "plagiarism".
The completion and operation of the Beipanjiang Bridge not only realized the smooth flow of local transportation, but also strengthened regional economic and cultural exchanges, and played an important role in improving people's livelihood and developing the economy on the Yunnan-Guizhou Plateau.
This world-class miracle bridge has become a vivid footnote of the scientific and technological strength and people's wisdom of New China.
Beipanjiang Bridge: A miracle bridge connecting the Yunnan-Guizhou Plateau
The construction of the cable-stayed bridge, which spanned a 600-metre-deep canyon, posed a huge engineering challenge, and the piers needed to be erected on a steep canyon cliff, and the construction team overcame many difficulties to carve a level construction platform on the cliff before the piers could begin.
In order to ensure the quality of concrete, engineers have developed a "smart concrete", which can automatically flow and evenly fill into the mold, which greatly improves the construction quality and saves a lot of labor costs.
The engineers also adhere to the concept of low cost, low pollution and low energy consumption to reduce the impact of construction on the ecological environment as much as possible. They investigated the local climate characteristics and adjusted the construction plan according to the temperature changes in different seasons to ensure the bridge's wind and frost resistance.
Strict control of noise pollution, and the classification and recycling of waste generated by construction, to maximize the protection of ecological resources on both sides of the Beipan River.
After the completion of the bridge connecting Yunnan and Guizhou, the driving time between the two places was immediately reduced to several minutes, and transportation became extremely convenient.
The villagers of Puli Township and Duge Township are no longer blocked, and economic exchanges are more frequent. Many villagers, who have been living in hardship due to inconvenient transportation, have been lifted out of poverty and their quality of life has been greatly improved.
The development of the two counties has also gradually merged to form a unified economic zone.
Today, the Beipanjiang Bridge has become a new landmark of the Yunnan-Guizhou Plateau, attracting a large number of tourists from all over the world every year to come to see the Gaoqiao style.
The two places have developed special tourism projects, which have led to the development of service industries such as catering and accommodation, and provided jobs for ordinary people.
The Beipanjiang Bridge has also promoted the construction of transportation networks in Yunnan, Guizhou and even many southwestern provinces, becoming an important part of the mainland expressway system and making significant contributions to the national economic development.
The world's tallest cable-stayed highway bridge is not only an outstanding achievement in the field of structural engineering, but also allows the broad masses of people to enjoy tangible benefits.
It crosses the plateau and valley, connects the people of the two places, and also connects the beautiful life and development prospects.
epilogue
The completion of the Beipanjiang Bridge has indeed shortened the distance between Yunnan, Guizhou, Sichuan and Chongqing, and promoted the development of regional economy.
But we cannot deny that any infrastructure construction will have a certain impact on the ecological environment, bridges block the migration channels of animals, and change the river ecosystem.
This raises a question worth considering: how to balance environmental protection and sustainable development while pursuing economic benefits?
Perhaps considering wildlife access in the design of bridges and paying attention to environmental protection during construction are measures that we can take.
It is hoped that the Beipanjiang Bridge will not only bring economic dividends, but also live in harmony with the surrounding environment and realize the sustainable development of man and nature.
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