Core Points - The Wuhan Metro Line 12 has reached a critical milestone with the successful launch of the right-line tunnel boring machine, entering the dual-line synchronous excavation phase between Hangang Station and Hanxi Road South Station [1][3] - Once completed, the metro will allow passengers to cross the Han River in approximately 2 minutes, enhancing the efficiency of cross-river transportation in Wuhan [1] Construction Details - The tunnel section is a key control project, constructed by China Railway's subsidiary, China Railway Construction Investment, with China Railway First Group as the contractor [3] - The left tunnel is 1,372 meters long, and the right tunnel is 1,379 meters long, requiring the boring machine to operate approximately 30 meters underground through a clay layer and under 10 significant structures, including the Han River and Metro Line 1 [3] - To minimize ground disturbance during the dual-line excavation, a staggered launch plan was implemented, with the left line starting on October 20 and the right line on October 31 [3] Geological Challenges - The construction site presents complex geological conditions, including thick mud layers, loose sand layers, hard bedrock, and fractured zones, particularly under the Han River [3] - The underwater segment of the tunnel spans 347 meters, accounting for over 25% of the total length, with challenges such as a maximum cover depth of 41.2 meters and a maximum water pressure of 0.4 MPa [3] Safety and Quality Control - The construction team employs real-time monitoring of river surface dynamics, optimized boring tools, and a composite reinforcement technique to ensure safety and precision during excavation [3][4] - The project manager, a young professional with ten years of experience, emphasizes a "five no" quality standard: no pollution, no misalignment, no damage, no leakage, and no exceedance, which is integrated throughout the construction process [4][5]