铁龙过江，见证水下盾构技术跃迁（经济新方位）

Core Points - The successful completion of the Chongqing Caiyuanba Yangtze River Railway Tunnel marks a significant advancement in China's underwater shield tunneling technology, being the first high-speed rail tunnel to cross the Yangtze River [3][12] - The tunnel, approximately 11.9 kilometers long, connects the Yuzhong District and the Nan'an District of Chongqing, navigating through complex geological conditions including mountains, urban areas, water bodies, and the main channel of the Yangtze River [3][4] - The project utilized domestically designed large-diameter slurry balance shield machines, showcasing China's advancements in tunneling technology and equipment [5][12] Technology and Equipment - The "Yangtze" shield machine, with a diameter of 12.66 meters and a total weight of about 3,500 tons, features a high-precision pressure balance control system to manage the significant water and soil pressure encountered during tunneling [5][6] - Innovative techniques such as precise tunnel axis control and intelligent shield management systems were employed to ensure accurate navigation and tunneling, minimizing risks from surrounding structures and environments [6][8] - The project demonstrated the ability to assemble and operate the shield machine entirely underground, which is a first for high-speed rail projects in China [7] Industry Development - The construction of underwater tunnels is recognized as a highly challenging task, often referred to as "dancing on the edge of a knife," due to the complex geological conditions encountered [8][9] - China has made significant strides in shield tunneling technology over the past two decades, transitioning from reliance on imported machines to developing and deploying domestically produced shield machines [12][13] - The industry has achieved a high level of self-sufficiency, with over 90% of components for shield machines being domestically produced, although challenges remain in the ultra-large diameter segment [13][14] Future Prospects - The successful implementation of the Chongqing tunnel project is expected to enhance connectivity within the region, facilitating faster transit between key railway stations [7] - The ongoing development of shield tunneling technology positions China as a leader in this field, with increasing applications in various infrastructure projects across the country [11][12]