Written by: Yong Li, reporter of Science and Technology Daily
Planning: Zhao Yingshu, Teng Jipu, Lin Lijun
Taking this high-speed train at a speed of 350 kilometers per hour across the Three Gorges, you can personally feel that the speed in Li Bai's poem "The apes on both sides of the strait can't cry, and the light boat has passed ten thousand mountains" is not an exaggerated rhetorical device.
This is the speed of China's high-speed rail brought together by technological innovations and breakthroughs in new equipment.
The 350 km/h high-speed rail is no stranger to Chinese people.
But along the Zheng-Chongqing high-speed railway all the way to the west, across the mountains and canyons from the Central Plains, the train suddenly plunged into the tunnel, then passed the bridge, and flashed by, the light and shadow in the car were mottled and flowed, as if taking passengers to a new world.
This is a "subway-like" high-speed rail, an engineering marvel that amazes the world, and a major transportation artery running through China.
This high-speed railway took 12 years from the survey and design to the completion of construction, and the construction period was as long as 6 years.
Crossing the Three Gorges, the Shu Road is no longer difficult. The Zhengyu high-speed railway has witnessed the growth of a generation of scientific researchers, the rapid development of my country's high-speed railway industry, and the solid steps of the Chinese nation on the road of great rejuvenation.
On June 20, the Xiangyang East to Wanzhou North Section of the Zhengzhou-Chongqing High-speed Railway (hereinafter referred to as the Xiang-Wan Section of the Zhengzhou-Chongqing High-speed Railway) was opened, and another fast passenger channel for going out in the southwestern region of my country, the Zheng-Chongqing High-speed Railway, was fully operational.
The Millennium Shu Road is no longer difficult
In the front of the moving light and shadow, Li Ningyun, the driver of the Chongqing Locomotive Depot EMU who was driving the first train of the Zhengyu high-speed railway, suppressed his excitement. For this moment, he practiced repeatedly for several months.
As a native of Yunyang, Chongqing, he also has a deep understanding of the people's desire for railways in the Three Gorges Reservoir Area.
Xiao Qiang, deputy chief engineer of Chongqing Branch of China Railway Second Academy and deputy general design director of Zhengyu high-speed railway, was also a passenger on that day.
During the joint debugging and testing stage, the car has been ridden many times, and the flash of light is enough to let him know where he is, which mountain and which deep valley.
He has witnessed the transformation of the Zhengyu high-speed railway from the design drawings into reality step by step. Every bridge, tunnel, and even every minute data is familiar to him, just like yesterday.
Starting from Chongqing North, the train galloped through the mountains and ridges all the way. After entering Wanzhou, the "Gaoxia Pinghu", the tunnels became more and more dense. Before taking a closer look at the beauty of the Three Gorges, the speeding train was loaded into the long tunnel, and suddenly the beautiful scenery Appeared in front of him again, but without waiting for the details, he entered another section of the tunnel.
"The Little Three Gorges Tunnel is coming soon?" Xiao Qiang thought.
18.954 km, 3 minutes 40 seconds.
In this way, the high-speed train passed through the Small Three Gorges Tunnel and passed through this high-speed railway tunnel with a speed of 350 kilometers per hour, the longest single-hole double-track in Asia.
The construction of this tunnel alone took three and a half years.
The sun and the moon are turning, and the arrows are urging frequently.
Years later, Xiao Qiang still remembers the thrill of that year.
The Zhengyu high-speed railway passes through one of the most complex geological conditions in the world.
The direction of the line should avoid widely distributed landslides, debris flows, collapses, karst water and other unfavorable geology, and reduce the risk of railway construction and operation from the design source.
The route design prepared by the team and the various schemes selected by the team add up to more than 8,000 kilometers in length.
The lines involved in each scheme require designers to conduct on-the-spot surveys over and over again.
Among them, the design route selection from Wanzhou to Wushan has undergone dozens of surveys, route selection, review, and route change.
There is Wanren Mountain above and a thousand feet of water below; between the two cliffs, a wide gorge holds a reed.
In 2008, when smartphones were not as popular as they are now, Xiao Qiang and his colleagues traveled all over the mountains and rivers along the route, weaving through the canyons relying on maps and contour lines.
In order to find out whether the tunnel is a bridge or a tunnel when it passes through the Zhongliang River canyon, Xiao Qiang and his team conducted a lot of research and entered the canyon with a depth of thousands of meters to check on the spot.
In the deep mountains and valleys, I do not know how many people have set foot on it for thousands of years.
"Our group moved step by step against the cliff, and walked along the cliff of the river valley. In front of it is the sheep intestines path hanging on the cliff, and at the foot is the abyss..." Xiao Qiang still had lingering fears when he recalled the past.
After on-the-spot inspection, they found that dangerous rocks stand above the canyon. If the high-speed rail bridge is allowed to pass here, it is easy to cause safety accidents due to natural disasters.
Therefore, they finally decided that the high-speed rail would pass through the valley here, and the two tunnels would be merged into one.
This provided support for the correct decision of the subsequent route plan, and the Small Three Gorges Tunnel was finally completed about a year earlier than the original design period.
There are countless cases of similar overcoming construction technical difficulties.
"One third of my working life has been dedicated to this railway." Chief Engineer of China Railway Second Institute Chongqing Survey and Design Research Institute Co., Ltd. (hereinafter referred to as China Railway Second Institute Chongqing Company), and the overall design director of Zhengyu High-speed Railway of China Railway Second Institute Zhou Dingxiang said with emotion.
He has been busy for the Chongqing-Hubei section of the Zhengzhou-Chongqing high-speed railway for 12 years. He has traveled to the Three Gorges Reservoir area and the western Hubei region countless times to investigate routes, but he has no time to visit the scenic spots.
With the opening of the Zhengyu Railway, he and his team members finally had the opportunity to take this high-speed rail designed by himself, and go to the Three Gorges for a walk and take a look.
In 2012, the trees in the deep mountains and valleys were just a flick of a finger; but when the project planning and design were carried out back then, the young men in their 20s were almost at their age.
It was their efforts that ensured the smooth completion of the entire project and accumulated valuable experience for my country's railway construction. They have also grown into the pillars of this country.
Solve the century-old problem of going east out of Bashu
Surrounded by mountains, the Sichuan Basin is rich and colorful, and it has also created the "Shu Road" that is difficult to climb to the sky.
In the fifteenth year of Jiaqing’s reign in the Qing Dynasty, Tao Shu, a Hunan native, once entered Shu to preside over the township examination. He recorded the path of entering Shu in his “Diary of Shu Fu”: detouring from Beijing to Xi’an, then from Chengdu, via Yibin to Chongqing, and finally along Yichang, Pass Jingzhou, take Fancheng, and return to Beijing from Baoding.
Tao Shu's diary truly reproduces the journey from Sichuan to Shu for thousands of years.
The only way to take the dry road is to cross the Qinling Mountains, and the only way to leave Bashu in the east is the Yangtze River waterway.
"I crossed Wu Gorge from Baxia, then went down to Xiangyang to Luoyang." More than 1,200 years ago, Du Fu figured out the fastest route from Chengdu to Henan via Chongqing, but he had to build a railway along this fastest route to get through this route. It has always been a problem to build a large passage from the southwest to the Central Plains.
Zhou Dingxiang opened the map and pointed it to reporters: the Xiangyang-Wanzhou section is located in the sharp transition area between the third step and the second step of my country's topography.
This line has passed through the Nanxiang Basin, the Daba Mountains, and the Sichuan Basin, and crossed many first-class tributaries of the Yangtze River, including the Han River, Shennong River, Daning River, Meixi River, Tangxi River, and Pengxi River.
Not only that, above the surface, the main stream and tributaries of the Yangtze River cut the mountains and mountains into the Three Gorges of the Yangtze River and canyons of various sizes.
The flight of the Yellow Crane is still too high, and the ape wants to relieve the sorrow and climb.
More than a century ago, the elders in Sichuan were eager to build a railway to open up the Basin and Shushui and rush out of the basin.
The scheduled route of the Chuan-Han Railway is from Chengdu to Hankou, Hubei via Neijiang, Chongqing, Kuizhou (now Fengjie), with a total length of about 1,980 kilometers, and was stranded due to various reasons.
"In the 1950s and 1960s, the design experts of the older generation of the China Railway Second Academy studied various directions of the Sichuan-Henan Railway on a large scale, mainly including the western route through Shiyan, Ankang and Dazhou, and the western route through Yichang and Fengjie. , Wanzhou's Eastern Route Plan." Xiao Qiang had heard his predecessors talk about this history when he first started working.
The final choice was the western route plan, which went through Xiangyang and Shiyan in Hubei, Ankang in Shaanxi, and then Dazhou in Sichuan and Guang'an to Chongqing.
The sun and the moon are moving, and the laws of the year are updated.
The burden of history has gone round and round, and it has returned to the shoulders of this generation of railwaymen.
With the rapid development of China's high-speed rail technology, the once dream is no longer an extravagant hope.
Take a look at this high-speed rail that just opened to traffic!
Before the completion of the Zhengyu high-speed railway, there are Baocheng, Xicheng, Xiangyu, etc. to choose from the railway passages from Chongqing north to Beijing.
Among them, the fastest route takes the Xicheng high-speed railway. The line goes through the Chengdu-Chongqing high-speed railway - Xicheng high-speed railway - Zhengxi high-speed railway - Beijing-Guangzhou high-speed railway. The whole journey is 2176 kilometers, and the one-way running time is 11 hours and 20 minutes. Chongqing can arrive at the fastest 6 hours and 46 minutes.
Some people say that this is a "subway-style" high-speed railway, and the proportion of bridges and tunnels (bridge-to-tunnel ratio) in the Xiangwan section of the Zhengyu high-speed railway is 97%.
Among them, the section from Wanzhou to Wushan is even rarer in the country: there are 32 bridges in this section, totaling 10.8 kilometers, accounting for 5.9% of the line length; 27.5 tunnels, totaling 169.7 kilometers, accounting for 92.3% of the line length; the total length of bridges and tunnels is 180.355 km, the bridge-tunnel ratio is as high as 98.34%!
In short, for passengers, more than 92% of the journey is in the tunnel, and most of the time, the train travels in the tunnel, just like the subway in the city.
What is the concept of 98% bridge-to-tunnel ratio?
Yin Zhibin, director of the line station road design department of the Chongqing Company of the China Railway Second Academy and deputy general design director of the Zhengyu high-speed railway, explained that this means that a 100-kilometer high-speed rail line has only a 2-kilometer roadbed.
The subgrade length of the section from Wushan to Wanzhou is 3.3 kilometers. To meet the high-speed rail entry and exit stops at a speed of 350 kilometers per hour, the station has extremely strict requirements on the project, and a straight section of at least 1.4 kilometers long is required. In order to meet the complex functions of the station, it is also necessary to Try to set it on the roadbed as much as possible.
That is to say, the 3.3-kilometer subgrade is not long enough for high-speed rail stations. Some of the high-speed rail stations are built on bridges, and even some sections extend into tunnels.
It is precisely because the Xiangwan section is so difficult to construct that it took 12 years from the survey to the completion of the construction, and the construction period was as long as 6 years, much longer than other adjacent sections.
Yunyang, Fengjie and Wushan, which are located in the heart of the Three Gorges, have no railways and no high-speed railways.
Fengjie County, which is known as "Kuimen is the best in the world", has suffered from traffic constraints for a long time. It takes more than 4 hours to reach the central city of Chongqing by expressway, and it takes more than 5 hours to travel from Wushan County, where the goddess has stood for thousands of years, to the central city of Chongqing.
The completion of the Zhengyu high-speed railway has ended the history of the three places without railways, and when it opened, it was a high-speed railway with a speed of 350 kilometers per hour, which brought the Three Gorges area, which was trapped in traffic, into the high-speed era.
"The Zheng-Wan section of the Zheng-Chongqing high-speed railway is the straightest and straightest, and it has opened up the high-speed railway from the east of Sichuan and Chongqing to the north." Zhou Dingxiang said that the Zheng-Chongqing railway is an extension of both the Yu-Wan railway and breaks the "broken road" of the Yu-Wan railway. ” phenomenon, which effectively fills the gap in the high-speed railway network in the junction area of Henan, Hubei and Chongqing and the Three Gorges Reservoir area, improves the level of regional connectivity, and realizes the integration of inter-city transportation functions and high-speed rail channels.
After the completion of the Zhengyu high-speed railway, it has become an important part of the riverside channel and the Hunan channel in the national "eight vertical and eight horizontal" high-speed railway network.
After the whole line is opened to traffic, the Central Plains urban agglomeration, the Chengdu-Chongqing economic circle and the Yangtze River Economic Belt will be more closely linked, forming a new pattern for the development of the western region in the new era, assisting the construction of the Chengdu-Chongqing economic circle, and promoting the development of the Yangtze River Economic Belt. Quality development is of great significance.
Technological innovation polishes the background of a strong country
Difficulty is the key word in the whole process of Zhengyu Railway construction.
There is no doubt that it was once considered a forbidden area for railway construction.
The Three Gorges region has high mountains and deep valleys, and its geological structure is extremely complex.
Kuimen is the hero of the world.
Kuimen was called Qutangguan in ancient times.
Since ancient times, it has been called "the throat of the four roads in the southwest, and the belt of Wu and Chu Wanli".
The high mountains on both sides of the Lingjiang River are the gates of the Yangtze River entering the Three Gorges from the Sichuan Basin.
Here, the Three Gorges are connected, the walls are steep and sloping, and stretch for seven hundred miles.
The road to Shu is difficult, but it cannot stop generations of builders from "dare to teach the sun and the moon to change the sky".
In 1952, the Chengdu-Chongqing Railway, the first independently designed and constructed railway in New China, was completed and opened to traffic; in 1958, a direct train from Chongqing to Beijing was opened; in October 1965, the Sichuan-Guizhou Railway was put into operation, and the entire line was electrified at the end of 1991; In 1978, the Xiangyu Railway was opened across the board.
After becoming a municipality directly under the Central Government, Chongqing railway construction has entered a stage of great investment, great construction and great development.
At the end of 2000, the construction of the Yuhuai Railway started, and the whole line was opened in 2007.
Since then, Chongqing has successively built the Sui-Chongqing Railway, the Xiang-Chongqing Railway Double Line, the Da-Wan Railway, the Chengdu-Chongqing Passenger Train, and the Yu-Wan Intercity Railway.
Since the 19th National Congress of the Communist Party of China, Chongqing has comprehensively rolled out the construction of the "mi"-shaped high-speed rail network, and railway construction has set off a new climax. High-speed rail hubs and railway lines such as Chongqing West Station, Shapingba Station, and Chongqing-Guizhou Railway have been built successively. High-speed railways from Chongqing to Qianjiang section, Yukun, Yuwan, Chengdawan and Chengdu-Chongqing middle line.
By the end of 2021, the total operating mileage of Chongqing railways will reach 2,394 kilometers.
Today, China has become a world-famous "infrastructure madman". The emergence of new technologies and new equipment has polished the background of a strong country.
In the construction of the Diaohe Super Bridge in Xinye, a new type of integrated machine for transporting and racking independently developed by China showed its capabilities. It only took 3 hours to complete the erection of a 900-ton box girder; the Meixi River Double-track Super Bridge is the world's first A high-speed railway bridge with a maximum span of 350 kilometers per hour using ballastless tracks, the bridge has a total length of 687.8 meters and a span of 340 meters. The bridge body draws a graceful arc between the mountains and mountains.
The Xiangshuwan Tunnel of the Zhengyu High-speed Railway is about 12.5 kilometers long. The engineers and technicians optimized the design scheme by adopting the "3-dimensional spatial line selection method of karst geology". Reduced engineering risk.
Fengjie Tunnel is the third longest tunnel on the Chongqing section of the Zhengzhou-Chongqing high-speed railway. The geology here is "powder in the wind and mud in the water", just like tunneling in a "tofu". The construction is very difficult, one can imagine.
Liu Jianhua, chief engineer of the Zhengyu Railway Project Department of the China Railway 16th Bureau, who is in charge of the Fengjie Tunnel Project, told reporters that the technical staff innovatively proposed a combination of "liftable and retractable arch frame" + "two-step four-step construction method" + "temporary inverted arch". The method is equivalent to arranging three rows of "elevating and shrinking arches" in the tofu, increasing the stress and elasticity of the tunnel, and at the same time increasing the support density, solving the "peeling, cracking and falling blocks" of large deformation, and by implementing "replacement arches" ", increase the "attached arch" method, and increase the size of the arch to increase the firmness of the surrounding rock.
This move will increase the tunnel excavation less than 20 meters per month to 45-50 meters, and the construction period will be advanced 3 months.
Still in the Little Three Gorges Tunnel, known as the Geological Museum, halfway through the construction, a "Cheng Yaojin" - a karst cave with a depth of more than 55 meters that can swallow the Leaning Tower of Pisa.
If the traditional method of drainage and grouting is adopted, such a deep cave will be a drop in the bucket. If one is blocked, there will be fears that the groundwater will find another outlet, which will affect the safety of the railway.
"After careful research with the project department, it was finally decided to build a bridge in the cave and cross the cave." Liu Baolin, chief engineer of the tunnel department of the Chongqing Company of China Railway Second Research Institute, introduced that the final plan is to set up two diversion tunnels and build one at the bottom of the tunnel with a span of A 24-meter cast-in-place prestressed concrete simply supported box girder crosses the karst cave and avoids tunnel settlement.
This bridge, which is only 24 meters in length, is the epitome of scientific research and technical personnel overcoming difficulties.
If you don't accumulate a few steps, you can't reach a thousand miles; if you don't accumulate a small stream, you can't make a river or sea.
Taking this high-speed train at a speed of 350 kilometers per hour across the Three Gorges, you can personally feel that the speed in Li Bai's poem "The apes on both sides of the strait can't cry, and the light boat has passed ten thousand mountains" is not an exaggerated rhetorical device.
This is the speed of China's high-speed rail brought together by technological innovations and breakthroughs in new equipment.
(Science and Technology Daily reporter Yang Lun also contributed to this article)