At 11:33 on July 30, the world's largest diameter high-speed railway shield machine "Linghang", independently developed by China, crossed the natural barrier of the Yangtze River and arrived at No. 2 shaft. Thus, the Chongtai Yangtze River Tunnel achieved a water section breakthrough, setting a new world record for a single-head continuous excavation of 11.325 kilometers by a 15-meter-class large-diameter shield machine, laying a solid foundation for high-speed trains to cross the Yangtze River at 350 km/h without deceleration.

The Chongtai Yangtze River Tunnel is a key control project of the Yangtze River high-speed railway corridor in China's "Eight Vertical and Eight Horizontal" high-speed railway network, and a critical part of the national "Two Major" project, the Shanghai-Nanjing section of the Shanghai-Chongqing-Chengdu high-speed railway, connecting Chongming in Shanghai with Taicang in Jiangsu. The tunnel integrates "five extremes" of construction conditions: extreme long distance, with the "Linghang" shield machine excavating 11.325 kilometers in a single head; extreme large diameter, with the cutterhead of the "Linghang" shield machine measuring 15.4 meters; extreme high speed, with the high-speed train crossing the river at 350 km/h; extreme deep water pressure, with the deepest point 89 meters below the Yangtze River bed and water pressure of 0.9 MPa; extreme large shaft, with the "Qiming" boring machine having a diameter of 24 meters and No. 2 shaft being 56.08 meters deep.

Currently, the "Linghang" has successfully crossed major risk areas such as the Yangtze River embankment, anchorage, main channel, and the Coilia nasus national-level aquatic germplasm resources protection zone, safely passing through the deepest point 89 meters below the riverbed and arriving at No. 2 shaft. The series of intelligent construction technologies developed and applied in the project have been included in the "China Shield/TBM Tunnel Intelligent Construction Blue Paper", leading China's shield tunnel intelligent construction into the 2.0 era.

It is reported that after the completion of the Chongtai Yangtze River Tunnel, the high-speed train from Chongming to Shanghai Baoshan Station via Taicang will take only 17 minutes, fundamentally transforming the cross-river transportation pattern, accelerating the construction of the "Yangtze River Delta on Tracks", and injecting strong momentum into the high-quality development of the Yangtze River Economic Belt.