On July 6, it was learned that the double-tube single-head excavation of the Zimuyan Extra-Long Tunnel, a control project of the Guizhou Wulong-to-Daozhen Expressway, has recently surpassed the 5,000-meter mark.

New progress at the Zimuyan Extra-Long Tunnel on the Wudao Expressway

The Zimuyan Extra-Long Tunnel is a separated extra-long tunnel, with a left tube totaling 7,385.5 meters and a right tube totaling 7,401.5 meters. It passes through 2 synclines and 3 fault fracture zones, as well as more than 40 karst caves of various sizes, including karst water inrush, large karst cavities, and large mud inrush, making it the largest control project and a major difficult project on the Wudao Expressway.

The tunnel is divided into a Chongqing section and a Guizhou section. The Guizhou section, constructed under Wudao Bid 1, has a left tube 5,348 meters long and a right tube 5,393 meters long, and is currently the longest single-end-excavated downhill tunnel under construction in Guizhou Province.

During construction, the contractor carried out routine quality and safety hazard inspections and rectification, and adopted multiple measures to ensure the steady progress of tunnel safety, quality, and schedule. At the same time, dynamic construction was strictly carried out following the principles of "weak blasting, short excavation, strong support, early sealing, and frequent measurement," successfully overcoming difficulties such as rockbursts, mud inrush, and complex geological and hydrological conditions. The project innovatively adopted a visual-cast polymer plug formwork sealing technology and used jig frames to position secondary lining reinforcement, making the tunnel management process visual, information-based, and intelligent, and improving construction efficiency.

Rendering of the Zimuyan Tunnel portal

It is understood that the Wudao Expressway is an important corridor connecting Guizhou and Chongqing, and is of great significance for further improving Guizhou Province's transportation infrastructure, enhancing the overall efficiency of the road network, and promoting economic development and transportation efficiency along the route. Once the tunnel is completed, the drive from Daozhen to Wulong will be shortened from the original 2.5 hours to 0.5 hours, bringing a more convenient and efficient travel experience to people along the route.