On July 14, 2020, the Hongdoushan Tunnel, a key control project of the Yunnan Dali-Lincang Railway undertaken by China Railway 10th Bureau, was successfully completed, marking the successful breakthrough of the tunnel excavation problem of toxic and harmful gases, the first in China and rare in the world, and laying a solid foundation for the early opening of the Dali-Lincang Railway.
The Hongdoushan Tunnel of the Dali-Lincang Railway is the only long tunnel encountered in my country's railway construction that brings together 8 kinds of toxic and harmful gases, long-distance large-scale strong water inrush, high ground temperature, and long-section granite alteration. The tunnel is located in Fengqing County and Yun County, Lincang City. It is 10,616 meters long, adjacent to the Lancang River, surrounded by mountains, and the geographical environment is extremely complex. In order to complete the more than 10 kilometers of tunnels, 37 kilometers of construction access roads were built.
The Hongdoushan Tunnel is called a rare "poison gas" tunnel in the world because it has the most types of harmful gases, the highest concentration, and the greatest degree of harm. Its extremely high-risk area for toxic and harmful gases is 4,210 meters long, and the highly dangerous area is 3,630 meters long. The highly dangerous areas above the high level account for 73.8% of the total length of the tunnel.
The complex working conditions put forward higher requirements for construction, whether it is the safety protection measures for personnel or the mechanical equipment during the construction process. After multiple reviews by many experts, it was decided to use Anhui Jarlo's wet spraying equipment with stable performance and reliable quality. During the entire tunnel support construction process, Anhui Jarlo's construction equipment played a huge role and also laid the foundation for the smooth penetration of the tunnel.
