In a significant development reported on April 7th by the official WeChat account of "Guozi Xiaoxin" ("State-owned Enterprise News"), the construction of the Jintang Subsea Tunnel of the Ningbo-Zhoushan Railway has achieved a major milestone with the successful hoisting of the cutterhead of the tunnel boring machine "Dinghai," signaling the commencement of excavation for the world's longest and largest diameter subsea high-speed rail tunnel.
The Jintang Subsea Tunnel, a pivotal project of the Ningbo-Zhoushan Railway, not only connects the two major cities of Ningbo and Zhoushan but also stands out for its remarkable specifications. With a total length of approximately 16.18 kilometers and navigating through complex geological conditions, it holds the distinction of being the world's longest, widest in diameter, and encountering the most intricate geological challenges, making it the most formidable subsea high-speed rail tunnel under construction today.
The "Dinghai" tunnel boring machine (TBM) that ventured underground this time boasts a colossal cutterhead excavation diameter of 14.57 meters, with a total length of around 135 meters and a weight tipping the scales at approximately 4350 tons. Comprising numerous intricate components, it's rightfully hailed as the "behemoth" among TBMs. Since its assembly line debut in Changsha back in January, this mammoth machine has traversed land and sea, spanning vast distances, and has finally arrived at the frontline of construction, primed and ready for tunnel excavation.
The assembly process of the "Dinghai" TBM is an intricate and intricate engineering feat. Since its arrival on January 28th, builders have meticulously planned each step of the assembly process, undergoing rigorous safety training and technical briefings to ensure precision at every turn. Through a series of carefully orchestrated maneuvers, the assembly tasks of the connecting bridge, gantry, and mainframe have been successfully completed, laying a solid foundation for the smooth descent of the TBM into the earth.
China Railway 11th Bureau Group Corporation (CR11BG), as the main force responsible for the excavation task of the Jintang Side Subsea Tunnel, boasts numerous internationally leading or advanced key technologies in the field of large shield tunneling. The National Digital Construction Technology Innovation Center and Intelligent Construction Laboratory for Shield Tunneling established by the bureau have played a crucial role in the selection, construction, and technological breakthroughs of the "Dinghai" shield tunneling machine, providing strong technical support for the "undersea journey" of shield tunneling machines.
The newly constructed Yongzhou Railway project is not only one of the top ten landmark projects in the construction of major thoroughfares in Zhejiang Province but also serves as a vital link in integrating Zhoushan City into the national development strategy. The opening of this railway will greatly promote the integrated development of Ningbo and Zhoushan, forming a "1-hour transportation circle" in Zhejiang Province, which holds profound significance for advancing regional economic integration and development.
