The Qinghai-Tibet Railway starts in Xining City, Qinghai Province and ends in Lhasa City, the capital of Xizang Autonomous Region, with a total length of 1956 km.
The Golmud-Lhasa section of the second phase of the Qinghai-Tibet Railway under construction, with a total length of118km, is a landmark project for China's western development. The Jiela section starts from Golmud, a new industrial city in Qaidam Basin in western Qinghai, passes through Nachitai, Kunlun Mountain, Wudaoliang, Tuotuo River and Yanshiping, passes through Tanggula Mountain, and then passes through Amdo, Naqu, Dangxiong and Yangbajing in the northern Tibetan Plateau, all the way south to Lhasa. It will cross more than 550 kilometers of permafrost, with an average elevation of more than 4,500 meters, and the highest track will cross the Tanggula Pass at an altitude of 5,072 meters. The total investment of this steel artery is 262 1 100 million yuan. It is planned to be paved in 2006 and the whole line will be completed and opened to traffic on July 1 2007.
Towering peaks, snow-covered areas, vast Gobi ... the ancient and mysterious Qinghai-Tibet Plateau has been silent and lonely for thousands of years. Although it is vast, beautiful and rich, in the past, due to the restrictions of economic, social and natural conditions, traffic congestion and poor logistics, people in the plateau could only adhere to the self-sufficient manor economy for a long time. Until 1949, there were only 1 km sidewalks for cars in Tibet, and the only water vehicles were cable bridges, cowhide boats and canoes.
In order to promote the economic development in the plateau area, as early as 1950s, the Party and the state made great efforts to study and solve the railway construction problem in Tibet. The Xining-Golmud section of the Qinghai-Tibet Railway started at 1958, stopped at 1960, and was rebuilt at 1974, and was completed and opened to traffic at 1984.
No railway in the world can give people such shock and excitement. In the Qinghai-Tibet Plateau, the most mysterious place except the moon, a world-famous steel dragon meanders forward, which will break through the forbidden zone of life, cross the Gobi Kunlun and fly over the rift valley ... It tells the world with indisputable facts that it is the plateau railway with the highest altitude and the longest line in the world!
■ Wind-volcano tunnel, the highest plateau permafrost tunnel in the world.
The Fenghuoshan Tunnel is located on the Fenghuoshan at an altitude of 50 10 meters, with a total length of 1338 meters and an elevation of 4905 meters, all of which are located in permafrost on the plateau. It is the highest altitude tunnel in the world and the longest tunnel across permafrost regions, and is known as the "highest tunnel in the world".
When I came to the Fenghuoshan tunnel, I was first attracted by the huge couplet in front of the tunnel entrance: "Take the white clouds to caress the blue sky, fight against the snow and bind the black dragon, and step on the breeze to invite the bright moon to pass through the world's highest tunnel." The climatic environment in windy and volcanic areas is extremely harsh, with an average annual temperature of minus 7 degrees Celsius and a minimum temperature of around minus 40 degrees Celsius, with severe cold and lack of oxygen.
More than 300 builders from China Railway 20th Bureau, Xianyang, Shaanxi Province took part in this tough battle to get through the wind and volcano tunnel. In order to solve the problem of plateau hypoxia, they built the highest oxygen station in the world. During tunnel construction, diffuse oxygen supply is carried out in the tunnel to increase the oxygen content in the tunnel, which fundamentally solves the problem of hypoxia in plateau construction. At the same time, China Railway 20th Bureau also equipped each dormitory with oxygen inhalation equipment and provided anti-hypoxia drugs to ensure that every employee can get enough oxygen. Thanks to scientific measures, the Qinghai-Tibet Railway was built. Although the construction conditions here are the worst, the incidence of altitude sickness among workers is the lowest in the whole line.
200 1 10 18, the first shot was fired in Huo Feng Tunnel, which caused shocking spoil. The soil content of these abandoned soils is about 15% to 20%, and the geological structure of the tunnel is mainly soil-bearing ice layer, saturated frozen soil, primitive glacier, fissure ice, sandstone, mudstone and sediment interbedded. Fenghuoshan Tunnel is listed as the first key project of Qinghai-Tibet Railway, and is known as "Tian Zi No.1 Project".
In order to ensure the construction quality, China Railway 20th Bureau invested more than 52 million yuan to purchase domestic first-class tunnel construction equipment, realized rail transportation in the tunnel, built a high-pressure steam boiler, heating station and heat preservation and cooling system in the tunnel, and solved a series of problems such as temperature control in concrete construction in the tunnel. On June 65438+1October 65438+September, 2002, Huo Feng Tunnel, the highest plateau frozen soil tunnel in the world, passed through.
■ Kunlun Mountain Tunnel, the longest plateau frozen soil tunnel in the world.
It snows in June at the entrance of Kunlun Mountain Tunnel at an altitude of 4,648 meters. It is cold and oxygen-deficient all the year round, the oxygen content is only half that of the inland plain, and the lowest temperature reaches MINUS 30 degrees Celsius.
The builders of the Qinghai-Tibet Railway who fought here braved the harsh natural environment of the Qinghai-Tibet Plateau to build the longest plateau frozen soil tunnel in the world. Tunnel construction in frozen soil area is much more difficult than that in plain area. Every summer, the temperature in the tunnel will rise, sometimes reaching about 7 degrees Celsius. At this temperature, frozen soil is easy to melt, and ice slag sometimes falls in the tunnel, which brings great difficulties to the construction. In order to prevent and reduce the influence of frozen soil diseases on tunnel stability, the construction of Kunlun Mountain Tunnel is twice that of plain area. Tunnel construction in plain area only needs to add a layer of concrete after bolting and shotcreting support, while tunnel construction in frozen soil area needs to set up two layers of waterproof layer and an insulation board to play a waterproof and thermal insulation role, and finally line with a layer of concrete. This is equivalent to putting waterproof and warm clothes on the tunnel, which effectively solves the construction problem of frozen soil tunnel.
In order to ensure the physical and mental health of construction workers, China Railway No.5 Bureau and No.4 Company has stipulated a four-hour shift operation system, which provides sufficient oxygen for the workers in the tunnel every day and regularly checks the air quality in the tunnel. At the entrance of Kunlun Mountain Tunnel, a yellow ventilation pipe runs through the tunnel like a ribbon, which continuously sends fresh air into the tunnel from outside the tunnel, ensuring the oxygen content in the tunnel construction. They also set up an emergency center at the tunnel entrance, a hyperbaric oxygen chamber at the construction site, and oxygen cylinders in the staff quarters. At the same time, employees are given a physical examination every quarter, and those who feel unwell are immediately sent to Golmud for treatment.
Kunlun Mountain Tunnel was completed on September 25th, 2002.
■ Tanggula Station, the highest railway station in the world.
On June 29th this year, Tanggula Station, the highest railway station along the Golmud-Lhasa section of the Qinghai-Tibet Railway, broke ground, which is also the highest railway station in the world at present.
Tanggula Station is located in the permafrost region of Tanggula Pass at an altitude of 5,068 meters, covering an area of about 77,000 square meters and designed as a three-lane highway. After the completion of Tanggula Station, it will mainly meet the needs of train transfer. The station was built by the Sixth Project Department under the 18th Bureau. According to the geographical location and geological characteristics of the station, flaky ventilation subgrade is adopted in the engineering design. This design can keep the frozen soil temperature relatively stable, thus reducing the disturbance to the frozen soil and achieving the purpose of effectively protecting the frozen soil.
When Tanggula Station was completed in August 2004, it will become a major scenic spot on the Li Qian-Qinghai-Tibet line.
■ China's largest plateau railway bridge base-Nanshankou Bridge Base of Qinghai-Tibet Railway.
About 30 kilometers south from Golmud City, the starting point of Golmud section of Qinghai-Tibet Railway, you will come to the China Railway Construction History's largest and highest-ranking plateau Pujia Base-Nanshankou Pujia Base of Qinghai-Tibet Railway at an altitude of 3,050 meters.
The bridge-laying and bridge-erection base at Nanshankou of Qinghai-Tibet Railway ranks first in the history of railway construction in China with its large scale and high technical content. At the beginning of the construction of the Qinghai-Tibet Railway, there was still yellow sand flying, inaccessible and desolate. Since the clarion call for the construction of the Qinghai-Tibet Railway sounded on June 29th, 20001year, more than 500 employees of China Railway No.1 Bureau have fought against anoxia, sandstorm and camping in this barren land, and launched a tough battle between man and nature, railway construction technology and management level, overcoming many difficulties and raising the banner of "leading" for the construction of the Qinghai-Tibet Railway.
The installation and debugging of machinery and equipment began in March last year, and the trial production of nailing production line began in April. Guo Xiuchun said that the Nanshankou Bridge Base undertakes the task of laying tracks and bridging the Nanshankou-Amdo section of the Qinghai-Tibet Railway. The Qinghai-Tibet Railway passes through the "roof of the world", which is characterized by cold, lack of oxygen and low pressure, as well as unfavorable factors such as large slope, large temperature difference, many sandstorms and lightning, which brings great difficulties to construction and transportation. At present, the power of domestic track-laying machines, bridge-erecting machines and diesel locomotives on the Qinghai-Tibet Plateau with an average elevation of 4,000 meters is reduced by nearly half, and the general maximum slope adaptability is 12 ‰. Moreover, due to lack of oxygen, insufficient fuel combustion produces a large amount of waste gas, causing environmental pollution. However, the maximum design gradient of the Qinghai-Tibet Railway is 20 ‰, and the harsh climatic conditions and special geographical environment have become the "obstacles" for railway track laying. To this end, China Railway No.1 Bureau mobilized experts with rich experience in track-laying and bridge-building, reformed domestic track-laying and bridge-building machinery and diesel locomotives, and put forward a series of specific solutions and measures, such as developing oxygen-supplementing and pressurizing equipment, reforming machinery and rolling stock equipment, and preventing severe cold, sandstorm and lightning. After the transformation, the track-laying bridge-erecting machine and diesel locomotive work on the slope of 22/ 1000, with good dynamic performance, normal equipment operation and little environmental pollution. This scientific research achievement fills the gap of domestic plateau bridge technology and provides equipment support for Qinghai-Tibet railway bridge.
Since the track laying of the Qinghai-Tibet Railway began on June 29th last year, China Railway No.1 Bureau has been pushing the Steel Avenue to Lhasa at the speed of laying 3,000 meters and bridging 3.5 holes every day. They set a record of 6,575 meters of track laying and 6.5 holes of bridge construction every day, which is basically equivalent to the speed of track laying and bridge construction in plain areas, and ensured safety and quality.
■ The longest "replacing road with bridge" project of Qinghai-Tibet Railway-qingshui river bridge.
Qingshui river bridge is located in no man's land at an altitude of more than 4,500 meters in Hoh Xil, with a total length of 1 1.7 km. It is the longest "replacing road with bridge" bridge on the Qinghai-Tibet railway, and it is also the key control project of the whole Qinghai-Tibet railway construction.
The Qingshuihe super-large railway bridge, like a beautiful "rainbow", flies in the core area of Hoh Xil National Nature Reserve with an average elevation of more than 4,600 meters. Here, Hoh Xil is cold and anoxic, with sparse vegetation and fragile ecology. At the same time, it is located in the plateau frozen soil area, with a frozen soil thickness of more than 20 meters and high ice content, which adds a lot of difficulties to the construction of the Qinghai-Tibet Railway. In order to solve the construction problems in plateau permafrost regions and protect nature reserves, experts in the survey and design of Qinghai-Tibet Railway adopted the measure of "replacing roads with bridges".
The seasonal temperature difference in Qingshuihe area is obvious, with the highest temperature reaching 38 degrees Celsius in summer and the lowest temperature reaching MINUS 40 degrees Celsius in winter. Under such climatic conditions, there will be hot-melt lakes, underground rivers, frost heaving and other phenomena in permafrost regions. In addition to hot-melt lakes and ponds visible on the surface, when the temperature rises in summer and the frozen soil melts, an underground river will be formed between 20 meters and 30 meters underground; In winter, hot melt lakes and underground rivers will form frozen balls protruding from the surface due to the sudden drop of temperature. If the frozen soil problem is not handled well, the railway will become a bumpy washboard road, leaving hidden dangers for operation. Due to the bad weather conditions, turtle lines appear on individual piers due to the cold weather. In order to ensure the quality of piers, the headquarters of China Railway 12th Bureau bombed three such piers.
Last year1October 29th 10, the main project of qingshui river bridge was completed. Under the Dragon Bridge, there are more than 1300 bridge opening between piers for the free migration of wild animals such as Tibetan antelopes. Now, the railway track has been successfully laid and passed through this bridge. In the mysterious and beautiful no man's land of Hoh Xil, the Qingshuihe Railway Bridge has become a charming landscape.
■ First Gao Qiao of Qinghai-Tibet Railway-Sanchahe Bridge
Walking15km from Nachitai on the northern edge of Kunlun Mountain, a magnificent bridge rises like a giant's arm holding up a speeding train. This bridge is the highest bridge along the Qinghai-Tibet Railway-Sanchahe Bridge. The total length of Sanchahe Bridge is 690. 19 m, and the bridge deck is 54. 1 m away from the valley bottom. It is the highest railway bridge on the Qinghai-Tibet Railway. It has 20 piers, of which 17 is a circular thin-walled hollow pier, and the thinnest part of the top wall of the pier body is only 30 cm.
Sanchahe Bridge is located in an alpine canyon with an altitude of more than 3,800 meters. The canyon formed by alluvial strata here is like a sharp axe splitting a high mountain from it, and the two ends of Sanchahe Bridge are suspended from a steep cliff.
The Third Company of China Railway 14th Bureau undertook the construction task of Sanchahe Bridge. In the mainland, it takes two years to build a bridge of similar size. However, this bridge is the key control project of Golmud-Lhasa section of Qinghai-Tibet Railway, which undertakes the task of laying tracks and erecting beams ahead, so the control period of bridge construction is only one year. In order to ensure the completion of the news, they have to hurry, even in the cold winter. 1 In February, the local temperature was as low as-30 degrees Celsius, so the problem of heat preservation must be solved first when pouring concrete for piers. After repeated experiments, they adopted methods such as steam insulation inside the formwork, cooking stoves outside the formwork, quilts and tarpaulins outside the formwork, and created a relatively warm environment in the ice world.
After the tenacious struggle of the builders, the Sanchahe Bridge started construction on August 22nd, 20001year, and was completed as scheduled on August 30th last year.
■ The first railway bridge at the source of the Yangtze River-Yangtze River Source Bridge
Standing in front of the environmental protection monument at the source of the Yangtze River, I saw a pier standing quietly in the river. Clear water flows downstream around the wharf. This is the first bridge at the source of the Yangtze River-the Yangtze River Source Bridge.
The Yangtze River Source Bridge is1389.6m long, with 42 holes in total, and spans a wide riverbed of about1300m. Tuotuo watershed where the bridge site is located is a big river melting zone in the abdomen of permafrost region of Qinghai-Tibet Plateau, which has the dual characteristics of frozen soil and melting zone, which brings certain difficulties to the construction. Since the start of construction on 200 1,11October 24th, the construction of the Yangtze River Source Bridge has progressed very smoothly. The main project was completed on September 25 last year, more than 300 days ahead of the required date. At present, the bored piles of the whole bridge have passed nondestructive testing, and the qualified rate reaches 100%.
In the construction of the source of the Yangtze River, environmental protection is the most concerned. China Railway Third Bureau has taken various measures to protect the environment here from pollution. The mud produced in the construction of bored pile should be treated by secondary sedimentation, and it is strictly forbidden to directly discharge the non-precipitated mud into the river. The water separated from the sedimentation tank is used for subgrade construction and pavement sprinkling. Other wastes, waste residues, etc. should also be concentrated in the construction spoil ground for leveling. As for caring for local vegetation and not disturbing wild animals, it is the principle that all employees follow.
■ Railway construction project with the largest investment in environmental protection.
The construction of Qinghai-Tibet railway faces three major problems in the world railway construction, namely, fragile ecology, cold and oxygen-deficient environment and geological structure of frozen soil. In order to protect the blue sky, blue lake water and rare wild animals on the plateau, the Qinghai-Tibet Railway has invested more than 2 billion yuan in environmental protection alone, accounting for 8% of the total investment of the project. At present, it is the largest railway construction project invested by China government in environmental protection. It is the first time to introduce environmental supervision into national engineering construction and sign environmental responsibility letters with local environmental protection departments. Qingshui river bridge, located in the Hoh Xil National Nature Reserve, was first built by the Qinghai-Tibet Railway for the migration of wild animals such as Tibetan antelopes.
■ One of the railway projects with the highest treatment for migrant workers.
In order to overcome the harsh environment of cold and lack of oxygen and ensure the life and health of railway builders. For the first time in the history of engineering construction in China, the Ministry of Railways and the Ministry of Health jointly made detailed regulations on medical and health security, and invested nearly 200 million yuan to establish medical and health security points across the line. Nowadays, all key construction sections along the Qinghai-Tibet Railway are basically equipped with advanced equipment such as hyperbaric oxygen chambers, which effectively solves the problem of lack of oxygen for builders. Qinghai-Tibet Railway is also one of the railway projects with the highest treatment for migrant workers. The railway department has invested a huge sum of money to implement the three unification of "unified life, unified residence and unified diet" in the management of migrant workers; For the first time, the daily minimum wage for migrant workers was stipulated, and free medical insurance was implemented for migrant workers. In order to solve the frozen soil problem of the largest frozen soil research base in China and even in the world, since the construction of the Qinghai-Tibet Railway started, the Ministry of Railways has attached great importance to the frozen soil problem of the Qinghai-Tibet Railway, arranged hundreds of millions of yuan of research funds for frozen soil research, and organized experts from several scientific research institutions to conduct research on five frozen soil engineering test sections of the Qinghai-Tibet Railway, and obtained a lot of scientific research data and achievements. The frozen soil research of Qinghai-Tibet Railway draws lessons from the frozen soil construction experience of large-scale projects such as Qinghai-Tibet Highway, Qinghai-Tibet Oil Pipeline and Lanssila Optical Cable, and discusses and draws lessons from the frozen soil research achievements of Russian, Canadian and Nordic countries. At present, scientists in China have taken measures such as replacing roads with bridges, flaky ventilation subgrade, ventilation tube subgrade, gravel and flaky slope protection, hot rods, insulation board and comprehensive waterproof and drainage system, and made great progress in solving frozen soil problems. Qinghai-Tibet Railway has become the largest frozen soil research base in China and even in the world.
The Qinghai-Tibet Railway, the world's highest railway, has created a number of "firsts" at home and abroad in the construction process due to three world-wide problems: fragile ecology, cold and lack of oxygen and frozen soil.
In terms of engineering construction, the total length of the Golmud-Lhasa section of the Qinghai-Tibet Railway under construction is1142km, crossing 960km above sea level, with the highest point being Tanggula Pass at an altitude of 5,072m, with an average altitude of 4,500m and crossing over 550km in permafrost regions. It ranks first in the world in terms of altitude, total mileage in high altitude areas and mileage in frozen soil.
The Tanggula Mountain Railway Station at an altitude of 5068 meters is the highest railway station in the world, and the Fenghuoshan Tunnel at an altitude of 4905 meters is the highest frozen soil tunnel in the world. Qingshui river bridge is located in the Hoh Xil National Nature Reserve, with a total length of 1 1.7km. It is the longest railway bridge built on plateau permafrost in the world, and also the longest "approach bridge" specially built by the Qinghai-Tibet Railway for the migration of wild animals such as Tibetan antelopes.
The Ando Pujia base at an altitude of 4,700 meters is the highest in the world. At an altitude of 3050 meters, Nanshankou Pujia base is the largest plateau Pujia base in Asia.
In the aspect of ecological environment protection, the whole process monitoring of Qinghai-Tibet railway construction: environmental supervision was introduced for the first time in the national engineering construction; Signing the environmental protection responsibility letter with the local environmental protection department for the first time; For the first time in the history of railway construction, the goal of "creating excellence and protecting the environment" was put forward. The first large-scale transplanting of turf; It opened the migration channel for wild animals for the first time. ...
Attaching great importance to environmental protection, the investment in environmental protection of Qinghai-Tibet railway construction is expected to reach more than 2 billion yuan, accounting for 8% of the total investment of the project. Lu Chunfang, commander-in-chief of the Qinghai-Tibet Railway Construction Command, said that it was the first time in the history of domestic construction that the investment and proportion of environmental protection were so large.
The Qinghai-Tibet Railway has also set many new records in paying attention to the life and health of builders. The Ministry of Railways and the Ministry of Health jointly issued a document for the first time in the history of engineering construction in China, which made detailed and specific provisions on medical and health security. For the first time, the Qinghai-Tibet Railway invested nearly 200 million yuan in domestic engineering construction, and established three-level medical and health security points along the whole line.
In addition, the Qinghai-Tibet Railway has become the largest frozen soil research base in China and even in the world. The investment in scientific research of Qinghai-Tibet Railway has exceeded 654.38 billion yuan. (Source: Xinhuanet Tibet Channel)
When the Qinghai-Tibet Railway was built at the door of the house, Awang, secretary of the Party Committee of Gulu Town, Naqu County, was somewhat worried: this is the most beautiful area of aquatic plants on the Qiangtang grassland in northern Tibet. Will building railways destroy grasslands? When railway builders built a railway station in Gulu Wetland, they invested 165438+ 10,000 yuan and successfully transplanted and built more than 80,000 square meters of artificial wetland. Awang breathed a sigh of relief: "Although the railway occupied some grasslands, the green here has not decreased." At present, the survival rate of lawn transplantation in Gulu wetland is over 98%, which has been integrated with natural wetland in plateau.
The total length of the Qinghai-Tibet Railway is 1 142 km, of which 960 km is built at a high altitude of more than 4,000 meters. In the past four years, 65,438+10,000 railway builders have solved the three world-wide engineering and technical problems of "ecological fragility, cold and hypoxia, frozen soil" with the spirit of "challenging the limit and creating first-class" and achieved remarkable achievements.
Plateau ecology has not been significantly affected.
Qinghai-Tibet Plateau is the birthplace of great rivers and is also an important origin center of mountain biological species in the world. Its ecological environment is primitive, unique and fragile. Before the railway started, the State Environmental Protection Administration, the Ministry of Land and Resources and the Ministry of Railways formed a joint expert group to conduct in-depth research on the eco-environmental protection work along the railway, formulate specific environmental protection measures, and arrange the budget for eco-environmental protection projects to be more than 654.38 billion yuan.
Cai Fan, deputy secretary of the Party Committee of the Qinghai-Tibet Railway Construction Command, said that in order to solve the problem of "ecological fragility", the railway was designed to minimize the ecological impact. In the nature reserve, the railway line is planned according to the principle of "avoiding as much as possible". The construction site, service road and gravel yard have been repeatedly surveyed to avoid destroying vegetation as much as possible. For areas where vegetation is difficult to grow, segmental transplantation is adopted during construction; For areas with slightly better natural conditions, turf is cultivated artificially. The contractor signed a letter of responsibility for environmental protection with the environmental protection departments of Qinghai and Tibet, and took the initiative to accept supervision and inspection. The whole line has also implemented the environmental supervision system.
The Qinghai-Tibet Railway passes through two national nature reserves, Hoh Xil and Qiangtang. In order to protect wildlife, 25 wildlife migration channels have been built along the railway. In June this year, the electronic monitoring of the Qinghai-Tibet Railway Construction Command confirmed that a large number of Tibetan antelopes migrated freely through wildlife passages along the railway. Investigations by the State Environmental Protection Administration and other departments show that the frozen soil, vegetation, wetland environment, natural landscape and river water quality along the Qinghai-Tibet Railway have been effectively protected, but the ecological environment of the Qinghai-Tibet Plateau has not been significantly affected.
Create a miracle of death without altitude sickness.
The section of Qinghai-Tibet Railway above 4000m above sea level accounts for about 85% of the whole line, the annual average temperature is below zero degrees Celsius, and the oxygen content in most areas is only 50%-60% of that in the mainland. Cold and lack of oxygen, sandstorms raging, strong ultraviolet rays and numerous natural foci are called the "forbidden zone" of human survival limit. How to ensure the life safety of builders in the harsh plateau environment is also a worldwide problem.
Cai Fan, deputy secretary of the Party Committee of the General Command, said that in order to solve this problem, all participating units adhered to the principle of "people-oriented, health protection first" and established and improved three-level medical security institutions. Medical institutions along the railway 1 15, with more than 600 medical staff, can get effective treatment within half an hour. At the same time, regular physical examinations are conducted for employees, and employees are arranged to take turns in low altitude areas.
During the construction of Kunlun Mountain Tunnel at an altitude of more than 4,600 meters, the constructors carried 5 kg oxygen cylinders and worked while inhaling oxygen. In the nearly one-year construction, * * * consumed 654.38+0.2 million bottles of 5 kg bottled oxygen. The 17th Bureau of China Railway installed an oxygen supply pipe in the dormitory of the construction site, so you can take oxygen at any time as long as you open the valve. During the construction of Fenghuoshan Tunnel at an altitude of 4,905 meters, a large-scale oxygen station was built in China Railway 20th Bureau to deliver oxygen to the construction tunnel, so that the oxygen content in the tunnel reached about 80%, which was equivalent to the elevation of the construction site being reduced by 1 1,000 meters. It is understood that 17 oxygen station has been built along the Qinghai-Tibet Railway, equipped with 25 hyperbaric oxygen chambers, and tens of thousands of employees take oxygen for at least 2 hours every day on average.
Under the strong medical security system, since the Qinghai-Tibet Railway started, more than 453,000 patients have been treated, 427 cases of brain edema and 84 cases of pulmonary edema1case, and no one died, creating a miracle in the history of plateau medicine.