A range of advanced shield tunneling technologies has been implemented at the construction site of the Jintang Subsea Tunnel, part of the Ningbo-Zhoushan Railway, according to China Railway 14th Bureau Group Co., Ltd. on Thursday. These innovations cover critical areas such as intelligent excavation and smart equipment, driving the development of the world's longest subsea high-speed railway tunnel toward unmanned and intelligent operations.

The Jintang Subsea Tunnel, a pivotal project of the entire Ningbo-Zhoushan Railway line, stretches from Beilun in Ningbo to Jintang in Zhoushan, spanning 16.18 kilometers in total. The shield tunneling segment measures 11.21 kilometers, utilizing two ultra-large-diameter tunnel boring machines (TBMs) that advance toward each other from the Ningbo and Zhoushan sides, ultimately achieving high-precision connection beneath the seafloor.

To address extreme working conditions, including ultra-deep positioning and high water pressure, as well as complex geological formations, the construction team has applied several domestically developed, independent innovative technologies. At the first Grand Shield Tunneling Summit, co-hosted by Southwest Jiaotong University, China Railway 14th Bureau, and China Railway Siyuan Survey and Design Group, He Chuan, an academician of the Chinese Academy of Engineering and chief professor at Southwest Jiaotong University, stated that the "Grand Shield Intelligent Driving System," which aggregates tunneling data from one-third of all large-diameter shield tunnels in China, is currently undergoing training and testing at the Jintang Subsea Tunnel.

This system integrates three intelligent modules: on-site perception, automatic excavation, and condition assessment and diagnosis. Staff can remotely monitor and control operations, or enable automatic shield tunneling when conditions are stable. Meanwhile, the "Shenyuan Large Model" for the shield tunneling sector has also entered trial use. This model incorporates extensive construction data and over 800,000 professional documents, leveraging an AI brain to facilitate intelligent decision-making in key areas such as risk pre-control, safety management, and tunneling supervision.

Additionally, the "Deep-Sea Space Station," China's first domestically developed saturated diving equipment for shield tunneling, has been officially put into operation at the site. Developed by China Railway 14th Bureau, the equipment includes fully self-reliant functional modules such as the Ninghai (living) chamber, Tanhai (shuttle) chamber, and Zhenhai (control) chamber. Core systems, including pressure control, gas management, life support, and emergency response, are all domestically developed, enabling pressurized cutter head replacement operations in ultra-high-pressure subsea environments and filling a technological gap in saturated diving construction for deeply buried tunnels in China.

Qian Qihu, a recipient of the State Preeminent Science and Technology Award and an academician of the Chinese Academy of Engineering, noted that intelligent development will be a major research focus in the shield tunneling field moving forward. Future steps should include enhancing the technical capabilities of intelligent cutter replacement robots, advancing the automation and intelligence of segment assembly in shield tunnels, strengthening automatic fault risk perception and control during excavation, and further expanding the application of smart technologies in complex tunnel construction projects.