At 10:30 a.m. on July 22, the left tube of the Chaoyang Tunnel on the Wuyunkai Expressway was accurately holed through. With this, the Chaoyang Tunnel, the longest tunnel on the Wuyunkai Expressway, has been holed through in both directions, marking a further step forward in the construction of the Wuyunkai Expressway.

Chaoyang Tunnel on the Wuyunkai Expressway holed through in both directions

The Wuyunkai Expressway is the 33rd link in Chongqing's "Four Rings, Twenty-Two Rays, Sixty Connecting Lines" expressway network and is a major municipal project. The project starts in Wuxi County, passes through Yunyang County, and ends in Kaizhou District, with a total length of 118.62 kilometers.

The Chaoyang Tunnel in Section B1 of the Wuyunkai Expressway is one of the controlling works of the Wuyunkai Expressway. It starts in Chaoyang Town, Wuxi County, and ends in Shangba Township, Yunyang County. The left tube is 5,110 meters long and the right tube is 5,132 meters long; the right tube was holed through on July 6. The tunnel connects Yuwu, Chaoyang and other areas, and is an important corridor for driving the development of impoverished townships along the route and accelerating the development of tourism resources in Hongchiba and along the line. It is also an important component of the major corridor that accelerates the connection between the main urban area and northeastern Chongqing and serves as a transit passage.

The average monthly advance of tunnel construction reached 143 meters, with the highest monthly advance in the arch frame section reaching 168.3 meters and the highest monthly advance in the smooth blasting section exceeding 206.1 meters, laying a solid foundation for the smooth progress of the project. At the same time, the project team has also actively explored the application of new technologies and new processes, continuously cultivating new quality productive forces. At present, the optimization of mechanized construction processes is being submitted for an invention patent.

During tunnel construction, the project team faced difficulties such as karst erosion areas and extreme rainstorm weather. In response, the project team adopted the double-layer arch frame method and the concrete filling method, and adhered to the principle of "treating every problem encountered" with strong support, strong drainage and full coverage when encountering karst caves, overcoming numerous difficulties. In addition, the project achieved fully mechanized operation in construction processes and implemented a small-team self-operation model in personnel deployment, greatly improving construction efficiency. Ultimately, while ensuring safety and progress, the project team completed tunnel construction 8 months ahead of the original schedule, with a total construction time of 32 months.

Construction site

At present, the overall progress of Section B1 of the Wuyunkai Expressway is advancing steadily. The Chaoyang Tunnel is expected to be fully handed over by the end of October and is expected to meet the conditions for opening to traffic by the end of the year.