On that day, the Chongtai Yangtze River Tunnel of the Shanghai Chongqing Chengdu high-speed railway, constructed by the Shanghai Hangzhou Passenger Dedicated Line Company and the China Railway Tunnel Bureau, broke through 5000 meters of excavation, leaving only 660 meters away from the river center. The Chongtai Yangtze River Tunnel is constructed using the "Navigation" shield tunneling machine, with a cutterhead diameter of 15.4 meters. It is equipped with innovative technologies such as intelligent excavation, intelligent assembly, and advanced geological prediction, and operates independently from Chongming, Shanghai to Taicang, Jiangsu in a "manned, unmanned" manner. It is currently the world's largest diameter high-speed rail shield tunneling machine. (Xinhua News Agency) Construction site of the "Navigation" shield tunneling machine segment hoisting for the Chongtai Yangtze River Tunnel of the Shanghai Chongqing Chengdu high-speed railway (photographed on March 16). A smart assembly mobile car with curved components is driving at the construction site of the "Navigation" shield machine in the Chongtai Yangtze River Tunnel of the Shanghai Chongqing Chengdu high-speed railway (photographed on March 16). This is the construction site of the "Navigation" shield machine for the Chongtai Yangtze River Tunnel of the Shanghai Chongqing Chengdu high-speed railway (taken on March 16th). This is the interior view of the Chongtai Yangtze River Tunnel formed by the Shanghai Chongqing Chengdu high-speed railway (taken on March 16th).