Zhanjiang Bay undersea tunnel shield tunneling machine successfully crossed the main channel of Guangzhou-Zhanjiang high-speed railway

At 10 am on September 13, "Yongxing" shield tunneling machine of Zhanjiang Bay undersea tunnel of Guangzhou-Zhanjiang high-speed railway successfully crossed the main channel of Zhanjiang Bay without any impact on the main channel of Zhanjiang Bay during the period, indicating that Zhanjiang Bay undersea tunnel has successfully overcome new technical difficulties and achieved a breakthrough.

Zhanjiang Bay undersea tunnel is a full-line control project, with a single hole and two lines, among which the shield section is 7,551 meters, the shield excavation diameter is 14.33 meters, and the outer diameter of the segment is 13.8 meters. It is the longest cross-sea high-speed rail shield tunnel with a single head at present in China.

The main channel of Zhanjiang Bay is the primary risk source of Zhanjiang Bay undersea tunnel project, and it is also the deepest crossing place. The operation, parameter control and equipment performance of shield tunneling machine are very strict, and the construction is faced with many difficulties and challenges. The pressure under the main channel of Zhanjiang Bay is higher, and the pressure performance of shield tunneling machine is faced with great test in the long distance driving at the bottom of the sea. At the same time, with the extension of the driving mileage, under the conditions of ultra-long distance drilling, material transportation, tool wear and tool change, mud pipeline explosion-proof, shield tail sealing safety, long-distance ventilation and other technical problems need to be solved one by one.

It is understood that the main channel of Zhanjiang Bay undersea tunnel through this time is 195 meters long, which is the most important maritime transportation line in Zhanjiang Bay. The maximum water depth is 20.8 meters, the lowest point is 16.7 meters, and the maximum water pressure is 6 bar.

In order to realize the smooth passage of "Yongxing" shield machine through the main channel of Zhanjiang Bay, the project strengthens the maritime monitoring and in-cave monitoring, implements 24-hour leadership monitoring and control, and invites shield experts to examine and discuss technical solutions, so as to ensure the completion of the task of shield underpenetration with the fastest speed and minimum disturbance.

At present, the "Yongxing" shield tunneling machine has drilled 2,770 meters in total, completed 1,385 rings, entered the sea section of more than 1,300 meters, and successfully crossed the deepest part of Zhanjiang Bay. It is expected to complete the overall tunneling task of the sea section by the end of the year.

Wide cham high-speed trunk line, about 401 km, line up the guangzhou railway station, foshan, zhaoqing, yunfu, yangjiang, maoming, zhanjiang city, eventually to north station in zhanjiang, zhanjiang hub in the west, to estimate the total amount of investment of 99.8 billion yuan, the design of train operation speed of 350 km, the longest mileage for guangdong province construction, investment, the biggest high-speed rail project.