In the grand blueprint of the national "Eight Verticals and Eight Horizontals" high-speed railway network, the construction of western railways is ushering in an unprecedented golden opportunity period. As a steel backbone connecting the north and south, the construction of the Beijing Kunming high-speed railway corridor not only carries the historical mission of breaking down geographical barriers such as the Qinling Mountains and Daba Mountains, but also serves as a key engine driving the deep integration of the three major urban agglomerations of Chengdu Chongqing, Guanzhong, and central Yunnan.

With the recent intensive construction of the Kangyu section of the West Chongqing High speed Railway and the Chongqing Kunming High speed Railway, this steel giant spanning Shaanxi, Chongqing, Sichuan, and Yunnan is growing at an astonishing speed, not only refreshing the "new scale" of engineering progress, but also injecting surging momentum into the high-quality development of the western region.

On January 29th, the Xuanhan Tunnel, constructed by Beijing Kunming High speed Railway Xikun Co., Ltd. and undertaken by China Railway Beijing Bureau, was safely completed. Thus, after 1068 days of fierce battle, all five tunnels (with a total length of 22.6 kilometers) under the jurisdiction of the five sections in front of the West Chongqing High speed Railway Station have been completed. As a single tunnel and double track tunnel adjacent to Xuanhan South Station, Xuanhan Tunnel has a total length of 5168.8 meters and faces complex geological challenges such as super large cross-section, shallow buried sections, low gas, bedding pressure, and rich water faults, resulting in extremely high construction risks. On the same day, the Gaosheng No.1 Tunnel, constructed by China Railway 17th Bureau, was also successfully completed. This 8392 meter long tunnel spans across Sichuan and Chongqing, and is a key node connecting the main line with the Wanzhou hub. The builders pierced through the hinterland of the Daba Mountains, overcoming 80% of the "natural dangers" such as IV and V grade surrounding rocks, rockfall from rock piles, and passing through high sulfur natural gas pipelines, finally making the natural ditch accessible.

On February 1st, good news came from the Hechuan East Tunnel of the West Chongqing High speed Railway. In response to the challenge of 96.7% extremely poor surrounding rock within the 7388 meter length of the tunnel, China Railway 14th Bureau has set up six working faces for synchronous excavation and carried out scientific and technological research, successfully overcoming the problem of salt soluble breccia becoming soft when exposed to water. The next day, the Jingzhuyuan Tunnel, the first long tunnel in Shaanxi Province on the Kangyu section of the West Chongqing High speed Railway, was completed. China Railway Tunnel Group has crossed synclines, anticlines, and faults within the territory of Langao County, overcoming the invasion of toxic and harmful gases and karst geology, and writing a wonderful footnote for construction in Shaanxi.

Turning to Yunnan, on February 3rd, with the final box girder accurately positioned at the construction site of the Chongqing Kunming high-speed railway, the construction of 117 bridges along the entire line was successfully completed. At this point, the bridge and tunnel project of the Chongqing Kunming high-speed railway has been basically completed, and it has fully entered the sprint stage of ballastless track and post station engineering. Keywords: Railway infrastructure, West Chongqing high-speed railway, Chongqing Kunming high-speed railway

The Xikun high-speed railway, as the backbone of the national "Eight Verticals and Eight Horizontals" Beijing Kunming corridor, consists of three sections: Xikang, Xiyu Kangyu, and Chongqing Kunming, with a total length of 1355 kilometers. With the expected opening of the Xikang high-speed railway in the second half of 2026, the completion of the Kangyu section by the end of 2027, and the basic completion of the Yikun section of the Chongqing Kunming high-speed railway in 2026, the time and space distance between Xi'an and Kunming will be compressed from 11 hours to about 5 hours. This steel artery not only connects the three major urban agglomerations of Guanzhong, Chengdu Chongqing, and central Yunnan, but also injects surging momentum into the high-quality development of the western region.Editor/Cheng Liting