"Jiangxi power" of super project -- the story behind the construction of Haoji Railway

On September 28, Haoji Railway (formerly Mongolian Chinese Railway), the world's longest railway and China's railway freight demonstration line, was officially put into operation. In China's railway territory, a new energy transportation channel has been added, which is running through the north and south, and it will be a great gift for the 70th anniversary of the founding of new China.

is a 1813.5-kilometer-long Haoji railway across seven provinces and regions, which fills the gap of the "north to South Coal Transportation" special line in China. As a heavy-duty freight line mainly for coal transportation, Haoji railway crosses the Yangtze River and the Yellow River, 229 tunnels and more than 770 bridges. The geology along the line is complex and the construction is difficult, so it can be called a super project. The Jiangxi Section of the

Haoji railway is 215 km long, located in Yichun, Xinyu and Ji'an City, while the most difficult section to be constructed is in section 32 of Xinyu City. As the person in charge of Haoji company said, "the construction of Haoji railway is difficult in Hunan Jiangxi section, and the construction of Hunan Jiangxi section is difficult in bid 32." Recently, the reporter came to Xinyu, approached the builder of Jiangxi Section of Haoji railway, and explored the story behind the construction of Haoji railway. Xu Wenjun, manager of No.1 work area of Nanchang company, No.32 section of Haoji railway of

China Railway 24th Bureau, introduced that Xinyu City is a typical karst landform, with thousands of karst caves scattered, known as "China's cave capital"; the company has 11 tunnels in No.32 section of Haoji railway, all in Xinyu City, with high gas, karst caves, karst cavities, water, mud, underground rivers and other complex conditions. I met them there. The

Haoji railway was officially started in October 2015. Xu Wenjun still remembers the scene of entering the project.

Beishan tunnel 2 is one of the typical tunnels. Its total length is 2398 meters, and it will encounter a karst cave 20 meters into the cave. After an average of 36 meters, it will encounter a karst cave of different sizes. As soon as the explosion goes down, the explosive dust rushes hard to the cave. At the bottom of the tunnel, a large karst cave with a buried depth of 30 to 40 meters and a vertical length of 75 meters along the line also emerges. Inside the cave, a milky white and golden stalactite is like a lifelike figure stone carving. A 6031 a 6031 "the most difficult construction of Beishan No. During the construction, the underground river flows out from the bottom of the tunnel with sediment. It merges into a torrent and rushes out of the tunnel. The maximum daily flow is more than 50000 cubic meters, which is equivalent to the amount of water that can flow out of Beijing Houhai in one month. " Xiao Changbai, deputy manager of the first work area, recalled. In charge of on-site construction, he wore rubber shoes to inspect various construction sites every day. He was often busy until one or two in the morning, and his feet were rotten.

in order to open the underground river area and excavate forward, the project department shall set up a temporary trestle crossing the underground river in the underground river area as a safe transportation channel for the continuous construction. After the tunnel is through, they take the scheme of "grouting reinforcement of steel pipe pile at the bottom of tunnel + lining reinforcement" to deal with the underground river section. Deng Changlin, chief engineer of the first work area of

, described their measures to deal with the dark river section. "In view of the complex geological conditions such as strong karst development, easily broken rock mass, and multi-layer karst cave superposition mainly composed of gravel and soft mud, the strategy of" rock change and self change "was adopted. According to the karst cave situation revealed in the design drawing, different types of drill bits were used to drill and steel casings with different diameters were used to follow up. It effectively avoids the occurrence of hole deviation, hole collapse, stuck drilling, buried drilling and other phenomena. " In addition, they also applied for the first time in China the technology of closed ring forming for the initial support of inverted arch, innovated and popularized the construction technology such as hydraulic self-propelled 24 meter long trestle, large-scale wet spraying manipulator, and applied for 4 patents, filling up the gap in the theoretical system and disposal technology of heavy-duty railway treatment of hidden karst caves in southern karst areas.

gas is the invisible killer of tunnel construction. There are three gas tunnels in the whole line of Haoji railway, and one in Jiangxi section. It is also a high gas tunnel that passes through coal measure strata and fault fracture zone. It is Shuanglin tunnel. In the construction, a scientific plan has been made in the first work area, with the gas advanced prediction and control as the key point, the coal seam gas content advanced prediction has been made by using seismic wave and advanced geological drilling, and the "double insurance" monitoring system has been established, which combines remote control automation system and manual on-site monitoring. Through various probes, we can know the gas concentration and wind speed of each part of the tunnel at any time. The gas detector uses portable gas detector and methane detector to detect continuously in 24-hour shifts. They also installed gas monitoring alarms on loaders, transporters and other construction equipment. When the gas concentration reaches the warning line, these equipment will automatically extinguish the fire, avoiding the explosion caused by the equipment fire source when the gas concentration rises. A 6031 a 6031 opened up a new road and built a bridge on the water. It took four years to build the Haoji railway, which left many unforgettable memories for the builders. Lin Ruhua, manager of No.5 work area of Haoji Project Department of

, recalled that since the project and Shanghai Kunming High Speed Railway meet, in order not to affect Shanghai Kunming passenger transport, from December 2017 to January 2018, they have experienced six times of closure construction of Shanghai Kunming railway, two times of which were attended by thousands of workers respectively, and the scene was very spectacular. Within two months, they not only completed the construction of two frame bridges under the Shanghai Kunming railway, but also completed the reconstruction of the Shanghai Kunming railway. In order to save time, they worked overtime 24 hours a day. They changed the original three times of construction of Underpass frame bridge to one time of pouring, and finally completed the task of Shanghai Kunming transfer line in advance. Behind the Haoji railway, there are a group of constructors who are dedicated to build the country as soon as possible. With 48 months of dedication and hard work, the builders have successfully crossed the "Dongdu city of China" with perseverance, wisdom and sweat, creating conditions for the completion and opening of the Haoji railway as scheduled. Haoji railway has become the coordinate to witness the struggle and dedication of railway builders. (Shi Huaxing, reporter Huang Ying)