The mined tunnel section of the Yungu Road municipal supporting project for Rail Transit Line 5, which passes beneath the Yungu Road Station on Line 1, has been successfully holed through. Unlike other sections, this section is Hefei's first mined tunnel to pass beneath an existing rail line.

The Line 5 tunnel passes vertically beneath the platform level of the Line 1 station. Although the underpass portion is not very long, the minimum cover at the structural crown is only 1.988 meters, far less than one tunnel diameter, making it an ultra-shallow-buried mined tunnel. In addition, the tunnel crown is subject to dynamic train loads, resulting in high risk, high difficulty, and a tight schedule. To ensure the operational safety of Line 1, this tunnel section was constructed using the manual mining method.

During an interview last month, the construction contractor stated that, in addition to building the Line 5 Yungu Road Station in advance, another important construction task was to complete the tunnel section passing beneath the Line 1 station before Line 1 entered trial operation. Now, the breakthrough of this tunnel not only eliminates the safety risks that Line 5 construction might pose to the trial operation of Line 1 and ensures that Line 1 can enter trial operation safely on schedule, but also accumulates valuable experience for similar projects in Hefei Rail Transit in the future.