Recently, construction of the Lingling–Daoxian Expressway in Hunan, an important link in the national expressway network, is proceeding at full speed. Among its sections, the Zijinshan No. 2 and No. 3 tunnel projects of the Fifth Contract Section stand out as the section's most brilliant milestones, cutting through towering mountains and rugged terrain at a remarkable pace to pave the way to the future.

Zijinshan No. 2 Tunnel

The Lingling–Daoxian Expressway in Hunan, with a total investment of 12.028 billion yuan and a main line length of 74.837 km, is not only an important part of China's transportation infrastructure construction but also a bridge connecting southern Hunan with the Pearl River Delta and Yangtze River Delta economic circles. The complex geological structure of Zijinshan has brought unprecedented challenges to tunnel construction; the tunnel lengths of 4.3 km and 3.9 km for No. 2 and No. 3 respectively represent not only a span of distance but also a dual test of technology and courage.

Zijinshan No. 3 Tunnel Cross Passage

Faced with difficulties such as variable geology, significant temperature differences, and severe dust, the project team of the Fifth Contract Section of the Lingling–Daoxian Expressway relied on technological innovation, adopting high-power axial flow fans to improve air quality inside the tunnels, using GPS positioning systems on dust masks and safety helmets to ensure worker safety, and continuously optimizing construction plans through high-frequency geological surveys and technical seminars, achieving a remarkable leap from 1.2 meters to 3 meters of daily advance.

The completion of the Zijinshan tunnels will greatly shorten the travel time between Lingling and Daoxian, promoting deeper regional economic integration and making daily life more convenient for residents. At present, the Zijinshan tunnel project is advancing rapidly and is expected to be completed and opened to traffic in the near future.