On January 27, the Gaojiashan Tunnel on the Chengdu-Dazhou-Wanzhou High-Speed Railway was holed through, marking a phased victory in the construction of Section 14 of the Chengdu-Dazhou-Wanzhou High-Speed Railway project.

The Gaojiashan Tunnel is located in Baiguo Village, Tingzi Town, Dazhou Eastern Economic Development Zone. It is a single-tube, double-track tunnel with a total length of 450.46 meters. The tunnel is a micro-gas tunnel, and the entire tunnel consists of shallow-buried sections, with a maximum burial depth of approximately 27.5 meters, posing high safety risks and great construction difficulties. The project department organized construction using a single-direction excavation method.

"During construction, we strictly followed the construction principles of 'advance pipe forepoling, short advance per round, weak blasting, strong support, early lining, and frequent measurement,' strictly adhered to the red lines of quality and safety, implemented environmental and water conservation management measures, and leveraged the effectiveness of standardized management, laying a solid foundation for the smooth holing-through of the Gaojiashan Tunnel," introduced Shi Jianzhi, deputy manager of the No. 2 Work Area of the Chengdu-Dazhou-Wanzhou High-Speed Railway Project Department of China Railway 18th Bureau Group.

The Chengdu-Dazhou-Wanzhou High-Speed Railway is an important component of the Yangtze River corridor of China's "Eight Vertical and Eight Horizontal" high-speed railway network. The main line has a total length of 477 kilometers and a design speed of 350 kilometers per hour. Once completed, it will form a convenient passenger transport corridor directly connecting Chengdu with the Central Plains and the Beijing-Tianjin-Hebei region, and is of great significance for promoting the construction of the Chengdu-Chongqing economic circle and the development of the Yangtze River Economic Belt.