On the morning of September 19, the "Jinggangshan No. 5" shield machine for Wuhan Rail Transit Line 12 was successfully launched, beginning its "underground journey" on the left line of the section from Qingling Station to Luojiaocun Station (referred to in this text as the Qing-Luo section).

Wang Bin, a Level-2 project manager of Wuhan Metro Co., Ltd., introduced that the "Jinggangshan No. 5" shield machine is an earth pressure balance shield machine newly developed by China Railway Engineering Equipment Group, with a cutterhead excavation diameter of 6.48 meters, a total length of 85 meters, and a total weight of 500 tons. "In August this year, this shield machine first completed the right-line tunneling of the Qing-Luo section, which is the first section of Line 12 to be holed through; it was then lifted out of the tunnel, relocated to Luojiaocun Station, and began the left-line tunneling task again."

"The left line of the Qing-Luo section has a total length of 883 meters. The shield machine needs to pass beneath a 110 kV power tunnel and a rainwater box culvert at close range, and to cross water-rich sand layers and mucky soft-soil unfavorable strata, so the construction risk is high and the difficulty is great," Wang Bin said. Even with the experience of successfully crossing on the right line, they still could not lower their guard.

A relevant person in charge of the project department introduced that the "Jinggangshan No. 5" shield machine customized for Line 12 is equipped with various advanced functions such as an intelligent tunneling management system, a muck metering system, and an automatic shield-tail clearance measurement system, and the shield machine has a relatively high level of automation and intelligence. "The shield machine's 'brain' has become smarter; it can calculate the actual muck output of each ring in real time, realize refined management of shield tunneling construction, reduce disturbance to the strata, and be safer and more efficient."

Wuhan Rail Transit Line 12 is a loop line with a total length of 59.9 kilometers and 37 stations. It links the three towns of Wuhan into a ring, passes through 7 central urban districts, and can transfer with 18 lines. The line crosses the Yangtze River twice and the Han River once. Wang Bin introduced that as of now, 15 shield machines are tunneling simultaneously underground along the entire line.

After Wuhan Rail Transit Line 12 is completed, it will effectively enhance the passenger flow attraction of the loop line, ease the passenger flow pressure in the central urban area, and be of great significance to accelerating urban economic development and improving the city's comprehensive transportation system.