China's tunnel boring machines equipped with "smart brains"

China's tunnel boring machines (TBMs) are now gaining "smart brains" through intelligent systems empowered by technologies like 5G, artificial intelligence (AI), and the country's BeiDou Navigation Satellite System (BDS).

A recent milestone in the industry was the launch of “Linghang," a super-large diameter slurry shield tunneling machine, in Chongming district, east China's Shanghai by the China Railway Engineering Equipment Group Co., Ltd. (CREG), a subsidiary of China Railway Hi-Tech Industry Co., Ltd. (CRHIC).

Thanks to an intelligent tunnel construction system, the machine boasts a "super brain" capable of independent thinking, intelligent analysis, and autonomous decision-making.

Photo shows a super-large diameter slurry shield tunneling machine named “Linghang.”Developed by the China Railway Engineering Equipment Group Co., Ltd. (CREG), a subsidiary of China Railway Hi-Tech Industry Co., Ltd. (CRHIC), the machine is equipped with advanced intelligent systems, including a smart excavation and intelligent assembly, and can enable autonomous or assisted tunneling. (Photo/Dong Chaowen)

"Linghang" can enable autonomous or assisted tunneling, marking a new high for China's intelligent shield tunnel construction capacity.

Its technologies concerning smart excavation, intelligent assembly, advanced geological forecasting, tail sealing safety warning, and online condition monitoring are leading domestic innovations.

"'Linghang' will lead China's intelligent shield tunnel construction capacity to new heights," said Jia Lianhui, chief engineer of CREG.

With over 20,000 components in a single TBM, intelligentization and automation have become inevitable trends to ensure the stability and geological adaptability of the machines.

The latest shield construction products manufactured in China are all equipped with intelligent systems.

On May 16, two shield tunneling machines named "Yongzhou" and “Dinghai," respectively, were officially started, working in two construction sites across the sea to build the Jintang undersea tunnel linking the Jintang islet of Zhoushan city, east China's Zhejiang Province, and the coastal area of Zhejiang's Ningbo city.

During tunneling operations, the digital TBM systems and intelligent devices of the machines enable real-time data collection, analysis and early warnings to accurately guide excavation while adapting to different geological conditions.

The two mega TBMs used in the Jintang undersea tunnel project, part of a railway connecting Ningbo and Zhoushan, need to cross under oil pipelines, seawalls, wharfs, shipping lanes, as well as other risky areas, and navigate 28 soil transitions, finally meeting 78 meters undersea with a centerline deviation within 2 centimeters — a feat made possible by intelligent guidance systems.

A TBM equipped with multiple intelligent devices is like "a mobile smart construction factory" working deep underground, said Hu Hao, commander of the Ningbo-Zhoushan railway project of China Railway 14th Bureau Group Corporation Ltd.

CREG has also developed the world's first green TBM that automatically optimizes excavation parameters to match subsurface conditions, maximizing efficiency while minimizing energy consumption. The machine rolled off the production line in May 2023, and was exported to serve the construction of tunnels along a high-speed railway in Italy's Sicily Island.

The intelligentization drive extends from equipment design and manufacturing to construction and maintenance across the entire tunneling industry chain in China.

According to Jia, CREG began research on the intelligentization of shield tunneling machines nine years ago.

In March 2015, the group's project, "Basic research on whole-process information-based intelligent control and supporting software for safe and efficient tunneling process of TBMs,” was recognized as a key national basic research development program.

The engineering team of CREG has achieved fruitful innovation results and technological applications, including the TBM-SMART system for intelligent tunneling control, which has been deployed on over 30 TBMs, and the TOMD system — the industry's first 24/7 "intelligent doctor”—which monitors key TBM components.

The group will witness a significant improvement in the intelligentization levels of TBM-related manufacturing and construction processes as tunnel builders and TBM manufacturers intensify cooperation with scientific research institutions, according to an executive of the China Railway Tunnel Group Co., Ltd.