China's latest intelligent shield tunneling technology has been successfully applied in the Chongtai Yangtze River Tunnel, a key project for the Shanghai-Chongqing-Chengdu High-Speed Railway. 

After working for over 2,000 meters, the shield tunnel intelligent construction V2.0 system was integrated into the "Pioneer" shield machine, significantly improving the efficiency and quality of the construction.

Shield Tunneling Construction Site of the Chongtai Yangtze River Tunnel [Photo provided to China.org.cn]

Designed for a speed of 350 km/h, the Chongtai Yangtze River Tunnel is the world's fastest underwater tunnel. It covers 14.25 km in total, including a 13.20-km-long shield section. 

Managed by Shanghai-Hangzhou High-Speed Railway Passenger Transport Co., Ltd. and constructed exclusively by China Railway Tunnel Group (CRTG), the Tunnel features a single-hole double-track design, with a shield diameter of 15.4 m and an outer diameter of the tunnel segments at 14.8 m, making it the world's largest diameter high-speed rail shield tunnel. 

Located at the deepest point of the Yangtze River with a maximum water pressure of 0.9 Mpa, the tunnel connects Chongming district in Shanghai with Taicang city in Jiangsu province.

With a single-headed excavation distance of 11.325 km, the longest in the world, the construction of the tunnel has involved the development and application of nine major intelligent construction technologies, including intelligent perception, design, prefabrication, excavation, installation, construction, environmental control, transportation, and management. An intelligent factory has been established for the automated production of shield tunnel segments and arc segments, marking China's first arc segment production line.

The fully intelligent "Pioneer" shield machine has now completed over 2,600 meters of excavation and is crossing the Yangtze River knifefish germplasm resource protection area with autonomous, safe, and stable "attended but unmanned" operation.

The Shanghai-Chongqing-Chengdu High Speed Railway is a vital part of China's "eight vertical and eight horizontal" high-speed railway network. The completion of the Chongtai Yangtze River Tunnel will enable high-speed trains to cross the Yangtze River without slowing down for the first time, creating a new fast channel between the Shanghai metropolitan area and the Nanjing metropolitan area. This project is crucial for implementing the national "Belt and Road" initiative, optimizing the railway network layout along the Yangtze River, and promoting the high-quality integrated development of the Yangtze River Delta.