On May 28, at the 20th Academician Conference of the Chinese Academy of Sciences, the 15th Academician Conference of the Chinese Academy of Engineering and the 10th National Congress of the China Association for Science and Technology, General Secretary Xi Jinping said that "the largest diameter shield machine started smoothly". The "Jinghua" jointly built by The Iron Construction Heavy Industry and the 14th Bureau of China Railway has attracted attention again, and the "Jinghua" is applied to the "Beijing East Sixth Ring Road (Beijing-Harbin Expressway ~ Luyuan North Street) Renovation Project" (hereinafter referred to as the East Sixth Ring Road Renovation Project) designed by the Tiesiyuan Consortium.
The scene of the off-line ceremony of the domestic largest diameter shield machine "Jinghua"
Combined with the construction of urban sub-centers, in 2019, beijing east sixth ring expressway is planned to transform and build a sixth ring park to effectively weave urban space, solve the problem of dividing the city of the expressway, guide the interactive development of urban functions on both sides and the agglomeration of innovative functions, and form an innovative development axis that runs through the historical status quo, the future, functional convergence, intensive and efficient innovation and development axis.
In June 2019, the design plan of the East Sixth Ring Road reconstruction project completed by the Tiesiyuan Consortium passed the review of multiple academicians and the dust fell to the ground, and it was determined that the transformation section into the ground adopted a super-large diameter shield plan.
According to the relevant design person in charge of the Tiesi Academy, during the implementation of the project design, it will face the five characteristics of "long, large, deep, multi and high".
"Long" - the total length of the tunnel section is 9.16 kilometers, and the shield section is 7.34 kilometers long, which is one of the tunnels with the longest single tunnel length of the super large diameter shield tunnel in China.
"Large" - shield tunnel segment outer diameter of 15.4 meters, shield machine excavation diameter of 16.07 meters, is the Chinese mainland developed and used so far the largest diameter shield machine.
"Deep" - the excavation depth, enclosure depth and maximum burial depth of the shield tunnel are the deepest in Beijing. Among them, the maximum burial depth of the shield tunnel is about 70 meters.
"Many" - down through 9 roads (bridges), 3 rivers, 3 railways, 1 high-speed rail station under construction, 1 rail transit line, 2 high-pressure gas pipelines, 3 housing buildings, 11 high-voltage electric towers, a total of 115 risk sources and 34 major risk sources.
"High" - This project is located in the sub-center of Beijing City, adjacent to the Beijing Municipal Government, with a high level of environmental protection, and is the first super large diameter shield project in Beijing, with high social attention.
In this regard, The Iron Construction Heavy Industry adopts a customized design, and configures a number of core technologies such as atmospheric pressure tool change, telescopic main drive, high-speed heavy-duty segment efficient reverse transportation and assembly technology, efficient and high-power slurry circulation system, high-precision excavation surface gas-liquid independent balance control, etc. on the "Jinghua"; at the same time, it is equipped with a number of core technologies such as pipe ring convergence measurement, pipe ring flatness detection, pipe ring selection, automatic shield tail gap measurement, synchronous double liquid grouting, three-way occlusometer tube change, etc., so that high strength, high risk, Highly polluting tunnelling operations have been transformed into a relatively safe and efficient green construction model.
The "Jinghua" shield machine is 150 meters long and has a total weight of about 4300 tons, which was jointly developed by the 14th Bureau of China Railway and China Railway Construction Heavy Industry in 9 months. This is the first time that Chinese enterprises have successfully realized the industrial manufacturing of 16-meter-class super-large diameter shield machines, and it is also the largest diameter shield machine developed in China so far.
In the next 2 years or so, the builders of the 14th Bureau of China Railway will drive the "Jinghua" shield machine to overcome many construction difficulties such as large excavation sections, dense above-ground risk sources, complex underground space environment, and long-distance crossing of water-rich and high-density sand layers, so as to help the construction of Beijing's urban sub-center.
Joining forces with strong forces, iron construction attacks. In recent years, Tiesiyuan, China Railway 14th Bureau and China Railway Construction Heavy Industry have started from nanjing Yangtze River Tunnel, and have successively completed the design of more than 40 large-diameter shield tunnels such as Wuhan Yangtze River Tunnel, Guangzhou-Shenzhen-Hong Kong High-speed Railway Shiziyang Tunnel, Hangzhou Qianjiang Tunnel, Wuhan Sanyang Road Yangtze River Tunnel, Jinan Jiluo Road Yellow River Tunnel, Jiangyin Jingjiang Yangtze River Tunnel, etc., and the projects are all over the first-tier cities such as Beijing, Shanghai, Guangzhou, and Shenzhen, as well as economically developed areas such as the Yangtze River Delta, the Guangdong-Hong Kong-Macao Greater Bay Area, the Middle Reaches of the Yangtze River City Cluster, and the Bohai Rim City Cluster.
Jiangsu Haitai River Channel Shenzhen Jihe High-speed He'ao Tunnel
In particular, tiesiyuan accounts for more than 45% of the design market of super-large diameter shield tunnels with an outer diameter of more than 14 meters, ranking first. The outer diameter of the jiangsu Haitai River channel pipe segment is 16 meters, and the length of the shield section is about 9300 meters, which is the longest and largest underwater highway shield tunnel in China; the outer diameter of the pipe segment of the Shenzhen Jihehe High-speed He'ao Tunnel is 17.5 meters, and the diameter of the shield machine excavation is expected to reach 18.1 meters, which is the world's largest shield tunnel, and in one fell swoop realizes the leap of the shield tunnel in the mainland from 16 meters to 18 meters, and writes the large-diameter shield chapter in the great rivers and mountains of the motherland, so that the golden business card of China Railway Construction is full of color.
Author: Liu Xinhong
Editor: Wang Ying, He Dacheng