From the mainland to Tibet, it was once difficult to get to the sky. Princess Wencheng has been to Tibet for more than two years. Now from Xining to Lhasa, the bus can run in two days. Drivers can let their "iron horses" gallop freely on the Qinghai-Tibet Highway. Drivers who drive at a low speed are often ridiculed by their peers as "old cows slow horses".
Wencheng should be safe and sound, and it will surprise the world-heaven and earth seem to shorten the distance between time and space because of the road! 1954, the Qinghai-Tibet highway with a total length of 1948 km was completed and opened to traffic. This road starts from Xining and passes through Golmud to Lhasa, which is the main national defense and economic road leading to the southwest frontier of the motherland. After several large-scale transformations and renovations, today's Qinghai-Tibet Highway is a highway that can enter and leave Tibet all the year round, bearing 85% of the passenger traffic and 90% of the freight traffic in the whole region, and is known as the "lifeline" of Tibet.
But how many people know how bad the road conditions on the Qinghai-Tibet Plateau are? How many people know what efforts and sacrifices highway engineers and technicians have made before knocking on the door of the "forbidden zone" and building this "road to heaven"?
Worldwide problems
Ice peaks, snow-capped mountains, storms, intense ultraviolet rays and severe hypoxia are natural signs of the Qinghai-Tibet Highway. Especially the section from Golmud to Lhasa, the altitude is between 4000m and 523 1 m.. It is necessary to cross Kunlun Mountain, Huofeng Mountain, Tanggula Mountain and Nyainqentanglha Mountain, and cross the plateau permafrost region with harsh ecological environment and complex geological conditions for more than 630 kilometers. A large area of continuous, island-like permafrost and seasonal permafrost, coupled with underground ice, ice piles, ice mounds, hot melt lakes and ponds and other adverse geological conditions, have formed the unique geology and landforms of the Qinghai-Tibet Plateau.
In the early 1950s, the strong voice of the development of New China knocked on the closed door of Tibet, and President Mao Zedong's order to "build roads while marching" awakened the quiet Qinghai-Tibet Plateau. 1954165438+1On October 25th, with the joint efforts of the PLA and engineers and technicians, the Qinghai-Tibet Highway was completed and opened to traffic. With the needs of Xizang Autonomous Region's economic development and national defense construction, 1972, the central government decided to rebuild the Qinghai-Tibet Highway, pave asphalt pavement and build permanent bridges and culverts.
This is a very challenging decision, and many people have doubts: there is no precedent in the world for paving asphalt pavement on plateau frozen soil. Can China people succeed?
Frozen soil is a kind of soil medium which is extremely sensitive to temperature. In winter, frozen soil, like ice at negative temperature, expands violently with the decrease of temperature, pushing the subgrade and pavement above. However, in summer, the frozen soil melts with the increase of temperature, and the roadbed settles after the volume decreases. This periodic change often leads to the collapse, subsidence, deformation and rupture of subgrade and pavement.
Paving asphalt pavement highway is equivalent to adding heat absorber and water sealing film on frozen soil, which makes frozen soil absorb heat and melt more in summer, and the moisture in subgrade cannot evaporate. This is a worldwide technical problem that has never been solved in the technical history of highway construction, and there is no successful technical data for reference. Over the years, Russia, Canada, the United States and other countries with large areas of frozen soil have been trying to find solutions, but the miracle has never appeared. The vast Siberia and other places have left deep regrets for road construction experts.
Because of the extremely important political, economic and national defense status of the Qinghai-Tibet Highway, ensuring its smooth flow not only affects the hearts of Tibetan compatriots, but also affects the hearts of the leaders of the CPC Central Committee, the State Council and the Ministry of Communications. 1973, the Ministry of Communications established the Qinghai-Tibet Highway Frozen Soil Research Group and allocated special funds to study the frozen soil problem of the Qinghai-Tibet Highway. Since then, the Ministry of Communications has invested a lot of special funds. Under the direct leadership of the Ministry of Communications, CCCC First Highway Survey and Design Institute (formerly the First Highway Survey and Design Institute of the Ministry of Communications) and other units systematically organized a complete set of technical research on highway construction in permafrost areas of the Qinghai-Tibet Plateau. During this period, three large-scale and systematic scientific and technological breakthroughs were carried out successively, and a series of scientific research papers, academic monographs and complete sets of applied technical achievements were obtained. These achievements have been applied in the reconstruction of the Qinghai-Tibet Highway, which provides a solid scientific basis for the reconstruction and reconstruction of the Qinghai-Tibet Highway in the hinterland of the plateau and ensures the smooth flow of the Qinghai-Tibet Highway.
Forbidden area exploration
The study of permafrost on Qinghai-Tibet Highway embodies the care and love of several generations in New China, the strong support of the Ministry of Communications and other national ministries and commissions, and the sacrifice and dedication of the vast number of traffic workers.
The reporter learned from a lot of information that many parties and countries have visited the Qinghai-Tibet Highway for decades. , Qian Yongchang, Huang Zhendong, Zhang Chunxian, Wang Zhanyi, Li Juchang, Hu, Feng, Li Jin, Yang and other dozens of department heads have given great attention and support to this research.
Under the direct leadership of the Ministry of Communications, 1973, the "Qinghai-Tibet Highway Research Group" composed of experts and scholars from the Highway Research Institute of the Ministry of Communications and the First Highway Survey and Design Institute of the Ministry of Communications set foot on the Qinghai-Tibet Plateau with an average elevation of more than 4,000 meters. From 65438 to 0999, the research group of Qinghai-Tibet Highway was struggling for lack of funds. Zhang Chunxian, then vice minister of the Ministry of Communications, said categorically: "Comrades of the Ministry of Communications should tighten their belts and support you in scientific research." In a word, researchers saw hope. Dr. Li, director of the frozen soil research executive office of China Communications First Highway Survey and Design Institute, is still moved in retrospect: "Because of this sentence, I gave up several opportunities to participate in other project research in recent years and insisted on doing frozen soil research with my comrades."
What a nice working environment!
In March and April, the mainland is in full bloom, but the Qinghai-Tibet Plateau is bitterly cold and snowy. The climate is more like the Monkey King's face. You change when you say it. Sometimes the sun is scorching, sometimes it is windy, sometimes it rains, sometimes it snows all over the sky, and sometimes it changes a dozen times a day. There are two folk songs that tell the sinister environment here: "There are no birds in the sky, and the wind blows stones away, wearing cotton-padded jackets all the year round, and there is not enough oxygen"; "After five beams, it's hard to see my parents".
Going to the Qinghai-Tibet Plateau, let alone engaging in scientific research, is a hero who can survive. Just boarded the plateau, nearly half of the members of the expedition team had a splitting headache, panting, weakness of limbs and loss of appetite. Some people barely ate a few mouthfuls of rice and vomited yellow water.
Severe altitude sickness tests the perseverance of researchers. For the sake of smooth roads and the travel of millions of Tibetan compatriots, they set up tents, cookers and camps at the foot of Li Xueshan. The night breeze made the tent "shout, shout" like an ice hole in the bed. Coupled with altitude sickness, researchers can't sleep at all. Sometimes tents are blown down by strong winds and there is no strength to get up and support them.
Working in the ice and snow, only white spots are found in the pickaxe, and machinery often goes on strike because of lack of oxygen. Researchers have to pick up cow dung, bake frozen soil, drill holes with steel drills and hammers, and collect scientific research data.
Sometimes when the wind reaches 1 12, it is "whistling", with snow and hail, no one can be seen 20 meters away, cars stop driving, and wild donkeys and antelopes also hide in the deep mountains. However, in order to obtain first-hand scientific research data, observers still have to stumble on the undulating Qinghai-Tibet Plateau, risk being swept away by the strong wind, lower the instrument tripod and kneel on the ground to read the data. They measured the changes of asphalt pavement meter by meter, and the cold wind blew through the leather coat, through the tight cotton-padded jacket and straight to the skin. It was the last straw. They ran around the car several times and broke out in a sweat to keep warm. Cold metal musical instrument, you can peel off a layer of skin as soon as you stick it on your hand, and stretch it into your arms to warm up before you work. If you are thirsty, you will melt snow water and ice water without water; Eat cold steamed bread when you are hungry. Ice buns like stones are often chewed for a long time without a bite.
Due to lack of oxygen, researchers have a terrible headache when thinking about problems, but they have to deal with a lot of data and study a lot of new problems every day, and their heads hurt like being sawed back and forth by a hacksaw, leaving many people with sequelae. Other plateau diseases such as heart disease, snow blindness and arthritis also threaten the health of researchers at all times.
On the long and desolate highway, researchers have to endure not only the torture of the environment and the test of physical labor, but also the inaccessible pain and boredom. In the mid-1980s, TV was popular in the mainland, but there was no TV signal on the plateau. The TV programs they saw at the nearby military station were usually recorded and sent from Xining a week or two ago. It takes at least a month for a letter to reach relatives in the mainland from the plateau. Many couples have been separated for a long time and lived a life of cowherd and weaver girl.
Speaking of plateau work, there is always a bitter word. Highway researchers on the plateau suffered a tragic misfortune. In the process of road construction, there are countless examples of how many people are working silently:
Wu Maomin, a national expert of China Communications First Highway Survey and Design Institute, devoted himself to the study of frozen soil on the Qinghai-Tibet Plateau at the age of 23. At the age of 74, he still has a soft spot for frozen soil, and has been to the Qinghai-Tibet Plateau nearly 100 times in decades.
Wang Zhongjiao, vice president of the First Highway Survey and Design Institute, has been involved in the frozen soil research on the Qinghai-Tibet Plateau since 2002, and has been traveling between An and the Qinghai-Tibet Plateau for several years, and his frozen soil research thesis has been awarded as an excellent doctoral thesis.
Zhang Zhongjiao, director of the Institute of Road Engineering in Cold Region of the First Highway Survey and Design Institute, 1984 studied permafrost in Qinghai-Tibet Plateau after graduation from university. In the past 20 years, most of his energy has been devoted to the study of frozen soil.
Dr. Li, director of the frozen soil research office of the First Highway Survey and Design Institute of China Communications, studied the frozen soil of the Qinghai-Tibet Plateau in his first job after graduation. ..
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In order to smooth the road, only the China Communications First Highway Survey and Design Institute invested 20 survey and design teams, and nearly 1,000 people undertook the survey and design tasks of the Qinghai-Tibet Highway project. Wu Shumin, Wang, Zhang, Li and other generations of researchers "dedicated their youth and their lives". Professor Wu Shumin suffers from lung disease, Director Zhang suffers from heart disease, and Dr. Li suffers from bronchitis ... But they have been insisting on frozen soil research on the Qinghai-Tibet Highway for decades, silently cultivating the land of life.
Due to the relatively slow change of frozen soil, it often takes years or even decades to collect and compare a set of data, and the research cycle is very long. It is a place where scientific research results are not easy to come out. While overcoming harsh conditions, it is more important for researchers to overcome the sense of loss and reputation in scientific research results.
What spirit makes these researchers willingly and silently dedicate themselves to this inaccessible place?
Zhang Zhao Jin, an honest man, thought for a long time and replied, "When you are on the plateau, you will feel that the sky is close to you and the mountains show you everything without reservation." Here, even the air is not enough, who will compete for pleasure, treatment and fame? Besides, if our professional highway survey and design personnel don't come to study, who will? "
Simple and unpretentious, with clear feelings and ambitions.
More than 30 years of efforts have achieved fruitful results.
For more than 30 years, several generations of researchers have been insisting on conducting field frozen soil surveys and experiments in plateau areas. In order to obtain the first-hand basic scientific research data, sometimes a group of people need to record the ground temperature, frost heave, thaw settlement and other data of hundreds of observation points regularly every day. Wu Shumin lamented: "The survey and observation data obtained on the Qinghai-Tibet Highway of nearly 2,000 kilometers is enough to fill several trucks!"
From 1973 to 1978, the research group of Qinghai-Tibet Highway Phase I put forward the design principle of "subgrade in plateau permafrost region with less frozen soil, more frozen soil sections and more thawing areas" on the basis of hard work and summing up practical engineering experience, and according to different foundation conditions and subgrade dry and wet types, it was concluded that "subgrade should be filled but not dug". These results provide a preliminary basis for the design and construction of the second phase reconstruction project of Qinghai-Tibet Highway.
The second research group of Qinghai-Tibet Highway 1979 to 1984 put forward the theory that the formation and melting of underground ice are the main reasons for the surface deformation and the destruction of engineering buildings in permafrost regions, and the distribution of underground ice is restricted by geological, hydrological and thermophysical factors. In the study of subgrade stability, improving subgrade is regarded as the basic measure to protect frozen soil; Nine economic and reasonable pavement structure combinations and some calculation parameters suitable for different zones in permafrost regions of plateau are put forward. For the first time in China, random polypropylene macadam mixture surface is adopted; Suggestions on pile foundation design in permafrost regions are put forward. These achievements have basically solved the technical problems of asphalt pavement construction, foundation design and construction of large, medium and small bridges in plateau permafrost regions, and met the needs of asphalt pavement reconstruction project of Qinghai-Tibet Highway.
During the third period 1985 to 1999, the research group of Qinghai-Tibet Highway conducted engineering geological exploration on permafrost by comprehensive means such as drilling, excavation and geological radar detection, and divided the permafrost along the Qinghai-Tibet Highway into high-temperature permafrost and low-temperature permafrost, and proposed that the dividing line should be-1.5 degrees Celsius. It is the first time to combine frozen soil temperature with subgrade design principle and integrate it into subgrade height design. It is the first time to put forward a new theory that the upper limit of permafrost in plateau can be allowed to move down appropriately by strengthening lateral protection without reducing the level of road service. Inorganic binder is applied to pavement structure in plateau permafrost region for the first time. For the first time, new technologies, new materials and new structures such as hot rod refrigeration, steel fiber cement concrete, EPS thermal insulation material, SBR modified asphalt and metal corrugated pipe culvert were introduced into highway construction. These research results provide necessary basis and data for the regulation project of Qinghai-Tibet Highway 199 1 to 1999.
From 200 1 up to now, combined with the western transportation science and technology complete set project "Study on complete sets of technologies for highway construction in permafrost regions", CCCC No.1 Highway Survey and Design Institute took the lead in continuously studying permafrost regions, which not only solved a series of problems existing in highway construction and maintenance in permafrost regions at present, but also promoted the further improvement of highway construction, management and maintenance technologies in permafrost regions.
There are new situations-overcoming technical problems-solving problems, and then there are new situations-overcoming technical problems-solving problems ... Researchers combine new requirements, use new technologies and materials, and negotiate the best harmonious coexistence plan with nature again and again. They persevered in harvesting rich fruits.
The first scientific research achievement of the Qinghai-Tibet Highway, hosted by China Communications First Highway Survey and Design Institute and undertaken jointly with other scientific research units, won the Major Achievement Award of the Ministry of Communications. Article 2 The scientific research achievements of Qinghai-Tibet Highway won the first prize of National Science and Technology Progress Award and the first prize of Science and Technology Progress Award of Ministry of Communications with 1987 respectively. The scientific research achievements of the third phase of Qinghai-Tibet Highway reached the world advanced technology and won the second prize of Shaanxi Science and Technology in 200 1-2002. Recently, the book Highway Engineering in Permafrost Regions of Qinghai-Tibet Plateau, which summarizes the achievements from 1973 to 1999, was officially published, and Minister Zhang Chunxian personally prefaced the book.
At present, a series of major scientific research achievements have been applied to all previous reconstruction and renovation projects of Qinghai-Tibet Highway on a large scale, resulting in remarkable social and economic benefits.
The Golmud-Lhasa section of the Qinghai-Tibet Highway took the "crawling" road in the early 1950s, and it took 15 to 20 days. In the late 1960s and early 1970s, it took 8 days to 10 to take a trip to the sand road. In the late 1980s, it took about 4 days to walk along the asphalt road. At the end of 1990s, the Qinghai-Tibet Highway renovation project was completed, which increased the original average speed from 20 to 30 kilometers to 50 to 60 kilometers, and the distance of off-road vehicles was about 1 150 kilometers. During the construction of the Qinghai-Tibet Railway, the Qinghai-Tibet Highway not only ensured the normal demand for passenger and cargo transportation in and out of Tibet, but also met the demand for a large number of equipment, materials, living materials and personnel transportation during the construction of the Qinghai-Tibet Railway. According to the statistics of Wudaoliang Traffic Observatory of Qinghai-Tibet Highway, before the construction of Qinghai-Tibet Railway, the traffic volume of Qinghai-Tibet Highway increased by 4.7 times.
Lay the foundation stone for the Qinghai-Tibet Railway
The Qinghai-Tibet Railway is expected to be put into trial operation in July 2006. However, few people know that the grand plan to build the Qinghai-Tibet Railway has been put forward for decades, and the frozen soil problem is one of the "obstacles" because it has been stuck on paper. A large number of basic data and successful technologies of permafrost research on Qinghai-Tibet highway provide scientific practical basis and theoretical and technical reference for Qinghai-Tibet railway construction.
From 1999 to 200 1, during the pre-feasibility, feasibility and preliminary design of the Qinghai-Tibet Railway, the First Survey and Design Institute of the Ministry of Railways visited the Qinghai-Tibet Highway Research Group for many times, and hired experts such as Wu Maomin who had worked in the Qinghai-Tibet Highway Research Group for many years as consulting experts. In May, 20001year, the "Plateau Frozen Soil Area" of China Communications First Highway Survey and Design Institute was purchased in the form of technical service contract.
Wu Shumin devoted most of his life to frozen soil research, and achieved fruitful results. Up to now, he still serves as the consultant of the Railway Expert Advisory Group of the Academy of Railway Sciences, the senior technical consultant of the Qinghai-Tibet Railway Construction of the Da Qiao Bureau of the Ministry of Railways, and has taught many times to the engineers and technicians of the Qinghai-Tibet Railway. Teach the key technical theory of plateau frozen soil engineering accumulated by living in plateau all my life to my brother units, and make contributions to the rationality and feasibility of Qinghai-Tibet railway construction project.
There is still a long way to go.
Permafrost is very naughty. Affected by time and space changes and other factors, its "temper" is extremely complex and changeable, and it is difficult for people to understand it at once.
At present, under the long-term adverse natural factors and heavy traffic load, cracks, deformation, looseness and other diseases have appeared in the permafrost region of Qinghai-Tibet Highway. Frozen soil is widely distributed in China, accounting for 2 1.5% of China's land area and about 10% of the world's total frozen soil area. It is mainly distributed in the Qinghai-Tibet Plateau, the western mountainous areas, the Daxinganling and Xiaoxing 'anling Mountains in the northeast and the Songnen Plain in the north of China, and scattered in some mountainous areas in seasonal frozen soil. With the focus of national economic construction tilting to the central and western regions, it is imperative to develop cold regions, and the construction of highway transportation infrastructure in frozen soil areas is the most important and has a long way to go.
At the same time, the global climate is gradually warming, and the degradation of frozen soil is becoming more and more serious. Therefore, a more in-depth and systematic study of highway construction in permafrost regions is of great significance to the development and utilization of land resources in permafrost regions in western China and the realization of sustainable development, especially in politics, military affairs, economy and science and technology.
Researchers are continuing to explore the mystery of building roads on frozen soil along the laws of practice, understanding, re-practice and re-understanding.