Successfully digging through the Yellow Crane Tower Wuhan Super Tunnel
Science and Technology Daily (Reporter Wu Chunxin, Correspondent Zheng Wei, Yuan Liang, Liu Fuchang) On August 29, as the huge cutterhead of the “Mir” shield machine turned slowly, the south extension project of Wuhan Heping Avenue crossed the “First Building of the World” Yellow Crane The super-large tunnel of the building was successfully excavated in Wuchang District, Wuhan. The shield section is currently the largest single-tube double-layer tunnel on urban roads in China.
Fu Minggui, Secretary of the Party Committee and Chairman of Wuhan Urban Construction Group, introduced that the south extension project of Wuhan Heping Avenue has a total length of 3,042 meters. Because the ground does not have the conditions to build a trunk road, and at the same time, in order to avoid the impact on the ancient city of Wuchang, the construction of “ground + tunnel” is adopted. , Of which the shield tunnel section is 1390 meters long. “The launch of the’MiR’ is a milestone, marking that the project has entered a stage of comprehensive tackling.” He said.
The tunnel passes through sensitive areas such as the ancient city of Wuchang, Beijing-Guangzhou Railway, and Sheshan Scenic Area. It adopts a single-tube, double-layer, two-way six-lane highway design. The outer diameter of the tunnel segment is 15.4 meters, the design speed is 50 kilometers per hour, and an excavation diameter 16.03m mud-water balance shield machine construction. This is currently the country’s first two-way six-lane single-hole double-decker road tunnel and the largest single-tube double-decker shield tunnel in China.
According to Zhang Jianyong, the head of the South Extension Project of Heping Avenue of the 14th Bureau of China Railway, the tunnel is located in the core area of the city and crosses the stratum with complex geology. It is one of the projects with extremely high technical content and extremely difficult construction in China. As soon as the tunnel starts, it passes through the ancient city. There are more than 500 old buildings and many celebrities’ residences along the route, and the requirements for settlement control are particularly high.
Zhang Jianyong said that the strength of the rock passing through the section reaches 200 MPa, and there is still karst development in the section. If the shield machine excavation vibration is too large, it will disturb and affect the newly built subway tunnel. Therefore, it is extremely difficult to control the construction parameters of the shield machine.
In the face of complex tunnel problems, the construction unit organized the construction unit and the equipment manufacturer to jointly develop a “Mir” mud-water balance shield machine with a total length of 136 meters and a total weight of 4,700 tons.
The shield machine is equipped with a drilling and injection integrated advanced geological drilling rig and an advanced geophysical exploration system, which is the first domestic application of the shield machine. At the same time, in order to improve the adaptability of the shield machine in hard rock formations, the shield machine is equipped with 93 hobs, 186 scrapers, 16 sets of edge scrapers and 32 tearing knives, through expert technology control. The disk opening ratio is increased.
It is reported that the southern extension of Heping Avenue is planned to be an important urban arterial road from north to south, effectively connecting the ancient city of Wuchang and the Wuchang Binjiang Business District, adding an urban artery to the development of Wuhan. The entire project is scheduled to be completed and opened to traffic by the end of 2023.
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