Core Points - The construction of the Haitai Yangtze River Tunnel, the world's longest underwater shield tunnel, is progressing well, with the "Jianghai" shield machine successfully advancing 200 meters and breaking through the 100-ring milestone [1][10] - The tunnel, located in Jiangsu Province, spans 39.07 kilometers, with an underwater section of 11.185 kilometers, designed for a dual six-lane highway with a speed limit of 100 kilometers per hour [3] - The project faces complex geological conditions, including soft clay and high water pressure, necessitating the use of a domestically produced 16-meter diameter shield machine [6] Engineering and Technical Aspects - The "Jianghai" shield machine features advanced technologies, including a constant pressure cutter head and an online monitoring system, achieving world-class standards [6] - The project team has optimized construction methods to address challenges such as shallow cover and the efficient assembly of large prefabricated components, with the largest weighing approximately 45 tons [9] - The tunneling speed has improved from 4 meters per day to approximately 14 meters per day after overcoming initial challenges [9][10] Strategic Importance - Once completed, the tunnel will significantly reduce travel time across the Yangtze River, allowing vehicles to cross in just 10 minutes, enhancing connectivity between cities in the Yangtze River Delta [10] - The project is crucial for promoting the integrated development strategy of the Yangtze River Delta region and fostering cross-river urban integration [10]