On January 4, with the completion of the last concrete pouring, the bottom plate of the main structure of the middle wind shaft in Jiangxinzhou of the second phase of Metro Line 4 was completed, which means that the main structure was completed, providing the necessary conditions for the shield machine to cross the Yangtze River next. It is understood that this wind shaft is about 44 meters deep, which is the control project of the second phase of Line 4 and the deepest foundation pit in the soft soil layer of the Nanjing Metro Project.
Adjacent to the Yangtze River and Jiajiang River, surrounded by water on three sides, the wind shaft is located at the northernmost end of Jiangxinzhou, less than 200 meters away from the river embankment on the east and west sides, and the extra-large depth and special location bring a series of challenges to the construction.
The depth of the ordinary foundation pit of Nanjing Metro is only 20 meters - 25 meters, which is equivalent to the height of an 8-story building, but the depth of the foundation pit of the wind well in the middle of Jiangxinzhou is about 44 meters, which is equivalent to the height of a 15-story building, which can be described as the deepest soft soil foundation pit in the history of Nanjing Metro. The on-site project engineer said.
The "main frame" of this wind shaft consists of 66 sheets and 64 meters deep5 meters, 1 thickIt is composed of a 5-meter, 180-ton reinforced concrete diaphragm wall. On the perimeter of the diaphragm wall, there is also a thickness of 0The 8-meter water-stopping plain concrete wall is used to isolate the river and sand with a double barrier.
The concrete-filled steel tube permanent structural column in the air shaft plays a vital role in the stability of the structure, and its verticality should reach one thousandth. With the help of innovative equipment such as universal vertical adjustment platform and inclinometer, the construction personnel followed the strict quality control process to achieve high-precision installation of ultra-deep and large-diameter concrete-filled steel tube columns, so that the actual verticality of the permanent structural columns reached 2/10,000, far exceeding the standard.
Ruilong Country Park Station - Shifosi Station Shield Tunnel.
Not only that, during the New Year's Day holiday, at the construction site of the negative three basement floors of Shifosi Station of Metro Line 4, the "New Journey No. 2" shield machine broke through the wall from the right line, marking the double-line breakthrough of the shield section between Ruilong Country Park Station and Shifosi Station.
Also during the holiday, the shield section of the right line between Xingzhi Road Station and Zhuozhuo Road Station of the first phase of Metro Line 11 was also completed. There is good news from the construction of both subways, and let's look forward to more construction progress in 2024
Material** Nanjing Metro, Hub Office.
Edit |Zheng Xiaoyang.
Release |Zheng Hao.
Audit |Liu Yuntao.