On April 13, with a resounding blast, the left tube of the Hejiang No. 3 Tunnel, constructed by the 15th Work Area Project Department of the Shaxi Branch Line of the Hejianlan Expressway, was successfully holed through, becoming the first tunnel on the entire line to break through. This marks a solid step forward in tunnel construction for the Hejianlan Expressway and achieves the “first good start” toward the goal of opening to traffic within the year.

　　The Hejiang No. 3 Tunnel on the Shaxi Branch Line adopts a separated design, with its exit located within Diantou Village, Shaxi Town. The left tube has a total length of 1,413 m, a maximum burial depth of 136 m, and an elevation ranging from 2,195.1 to 2,335.57 m. The tunnel area features steep terrain, large gradients, and complex geological structures. Faults and fissures are developed, and the surrounding rock has poor stability, resulting in considerable excavation difficulty and high risk. To ensure the milestone target was met on schedule, since excavation of the Hejiang No. 3 Tunnel portal began on May 3, 2020, the 15th Work Area Project Department planned ahead, conducted scientific assessment, and overcame technical difficulties. In sections with frequent karst caves, they adopted arch protection casting, sand-blow backfill support, and the three-bench excavation method with reserved core soil, advancing little by little and successfully completing construction in the complex sections, effectively driving the project forward.


　　According to project manager Shao Wanglin, the Shaxi Branch Line Project Department strictly followed the “four guarantees, one control, one cultivation” work requirements, scientifically planned and organized construction, and adopted targeted technical management measures in response to characteristics such as “fragmented, weak, and highly variable surrounding rock.” Following the principles of the “New Austrian Tunneling Method” and the concepts of “short advance, weak blasting, early support, and frequent measurement,” they continuously optimized construction organization and management during excavation, overcame a series of problems such as complex construction techniques and high difficulty coefficients, and over 345 days ensured the successful holing-through of the left tunnel tube under the premise of “zero accidents.”

　　At present, the Shaxi Branch Line of the Hejianlan Expressway has completed a cumulative investment of 760 million yuan. The entire project is advancing at full speed and will open to traffic by the end of this year.