On October 29, shield tunneling officially commenced for the Taihu Lake crossing tunnel of the Jiangsu Wuxi-Yixing Intercity Rail Transit Project (Wuxi-Yixing S2 Line), with two domestically produced 14-meter-class super-large-diameter shield machines, "Xianfeng" and "Xiwang," launching simultaneously. The tunnel, with a total length of 21.6 kilometers, is a controlling project of the Wuxi-Yixing S2 Line and the first super-large-diameter shield tunnel to cross Taihu Lake in China.
The two shield machines launched this time will respectively undertake the tunneling tasks for the land section between Mashan Station and the Zhushan Lake East Working Shaft, and the water section between the west Meiliang Lake Working Shaft and the central Meiliang Lake Working Shaft. The entire lake-crossing project plans to deploy four 14-meter-class super-large-diameter shield machines, with construction divided into five sections. The route crosses the Meiliang Lake and Zhushan Lake waters in the northwestern part of Taihu Lake and the Mashan area.
"Xianfeng" was developed by China Railway 14th Bureau Group in collaboration with CRCHI, with an excavation diameter of 14.02 meters, a total length of approximately 112 meters, and a weight of approximately 3,200 tonnes. In response to the uneven soft and hard ground conditions in the construction section, the equipment adopts a pressurized composite cutterhead equipped with various types of cutters including disc cutters and cutting bits, and is fitted with a high-power rock crusher, an intelligent excavation management system, and a segment uplift monitoring system. "Xiwang" has a maximum excavation diameter of 14.08 meters, a total length of approximately 132 meters, and a weight of approximately 3,600 tonnes, and is equipped with advanced geological prediction, guidance control, and simultaneous grouting systems.
The two launched shield machines are also equipped with intelligent tunneling technologies, including the "Shenyuan Large Model" and the Digital Intelligent Shield 2.0 system, integrating construction status perception, tunneling decision-making, and control functions. The construction support adopts environmentally friendly slurry circulation and slurry residue disposal technologies, implementing control over ground stability, tunnel formation, and water body protection during long-distance tunneling beneath the lakebed.
The Wuxi-Yixing S2 Line has a total length of 61.48 kilometers, a design speed of 160 kilometers per hour, and 9 stations, including 7 underground stations and 2 elevated stations. Upon completion, the line will connect Wuxi and Yixing and interface with existing and planned rail transit networks at nodes such as Taihu New City Station. According to the plan published by the Wuxi rail transit construction authority, the full journey from Yixing Station to Taihu New City Station is expected to take approximately 32 minutes.