Photo: Screenshot from China Media Group

The world's largest-diameter high-speed railway shield tunneling machine independently developed by China, "Linghang," for the Chongming-Taizhou tunnel under Yangtze River, marked the 10,000-meter tunneling milestone on Tuesday, with only 1,000 meters remaining to the southern bank of the Yangtze River. 

This is the first time worldwide that a 15-meter-diameter shield tunneling machine has achieved a single continuous tunneling of 10,000 meters, China Media Group (CMG) reported.

It is also a critical step for the tunnel project toward completing the "final kilometer" and achieving high-speed rail crossing the river at 350 kilometer per hour. Upon completion, the tunnel will significantly shorten the travel time between cities along the Yangtze River, such as Shanghai, Nanjing, and Hefei, better supporting the high-quality development of the Yangtze River Economic Belt, according to the CMG.

According to the Science and Technology Daily, the tunneling machine is equipped with the world's most advanced "brain" system, which has achieved breakthroughs in core technologies such as adaptive pressure control within the shield chamber, cloud-based predictive data self-decision-making and autonomous cruising of tunneling posture. Compared to manual operation, the parameters for tunneling, slurry circulation, and posture are more stable. 

It has enabled the routine application of fully algorithmic, unmanned intelligent tunneling across the entire system, setting a world record for monthly advance of 718 meters in a 15-meter-class high-speed railway tunnel.

Shield tunneling machines, formally known as tunnel boring machines (TBMs), are hailed as the "king of construction machinery" due to their immense scale and complexity. Once limited to horizontal excavation, today's Chinese-developed TBMs can operate in multiple situations - including vertical, inclined, and curved trajectories - earning the nickname "transformers" for the adaptability and precision, according to the People's Daily.
 
Back in October 2017, China's first domestically developed 15-meter-class slurry balance TBM, "China Railway 306," rolled off the assembly line, breaking the longstanding foreign monopoly in this field. Since then, China has successively rolled out the 15.8-meter "Chunfeng," the 16.07-meter "Jinghua," and the 16.6-meter-plus "Jianghai". Today, Chinese-manufactured TBMs account for nearly 70 percent of the global market, the People's Daily reported.



Global Times