Core Insights - The construction of the Hanjiang Tunnel for Wuhan Metro Line 12 has entered a significant phase, with the left tunnel's shield machine ready for operation, expected to reach Qiaokou District by March next year [1][2] Group 1: Project Overview - Wuhan Metro Line 12 is a key part of the city's "ring + radial" transit network, spanning approximately 59.9 kilometers with 37 stations [1] - The line will cross the Yangtze River twice and the Hanjiang River once, with the Hanjiang Tunnel being the last critical crossing point [1] Group 2: Engineering Challenges and Innovations - The Hanjiang crossing is described as the "throat" of the project, presenting significant construction challenges due to its geological conditions [1] - Two 6.8-meter diameter slurry balance shield machines are being used for the construction, which is equivalent to the height of a two-story building [2] - The project team has implemented several technical innovations, including upgraded shield cutter tools and a composite reinforcement technique involving "three-axis mixing piles + high-pressure jet grouting piles" to ensure stability [2] Group 3: Future Impact - Upon completion, Line 12 will connect seven central districts in Wuhan, linking major railway hubs and facilitating transfers with 18 other metro lines, enhancing commuter convenience and contributing to a "half-hour commuting circle" [2]