On April 22, the Shengjiazhuang Tunnel of the Xi'an-Yan'an High-Speed Railway, constructed by China Railway Third Group Co., Ltd. under the responsibility of the Shaanxi Co., Ltd. of the Xi'an-Chengdu Railway Passenger Dedicated Line, was successfully holed through, marking another major breakthrough in the construction of a long tunnel on the entire Xi'an-Yan'an High-Speed Railway line and laying a solid foundation for the orderly implementation of subsequent works.

The Shengjiazhuang Tunnel of the Xi'an-Yan'an High-Speed Railway is located in Yijun County, Tongchuan City, Shaanxi Province, with a total length of 7,060 meters. The tunnel passes through the low and medium mountain area of Ziwuling, where the terrain is undulating and the gullies are all V-shaped. The minimum buried depth of the tunnel is 22 meters, and the rock is relatively soft. The tunnel faces risks such as surrounding rock instability, collapse, roof fall, block falling, and layered peeling of the arch crown, making construction relatively difficult.

To ensure the smooth holing-through of the tunnel, the Shaanxi Company of the Xi'an-Chengdu Passenger Dedicated Line organized the project department to conduct comprehensive analysis and judgment of geological conditions through a combination of advanced geological forecasting and surrounding rock monitoring and measurement, so as to grasp in advance the location, nature and scale of unfavorable strata, optimize the advanced support forms and dynamically adjust blasting parameters. At the same time, through grid-based management and layer-by-layer on-site control, the smooth holing-through of the tunnel was ensured.

The Xi'an-Yan'an High-Speed Railway is the first high-speed railway in the old revolutionary base area of northern Shaanxi, an important component of the Baotou (Yinchuan)-Haikou High-Speed Railway corridor in the national high-speed railway network, and together with the Xi'an-Chongqing High-Speed Railway under construction, forms a major north-south corridor. It is an important part of the main framework of Shaanxi Province's "rice-shaped" high-speed railway network and a key construction project during the 14th Five-Year Plan period. The line has a total length of 299.8 kilometers, with construction standards for a double-track high-speed railway and a design speed of 350 kilometers per hour. After the line is completed and put into operation, the travel time from Xi'an to Yan'an will be shortened from the current 2.5 hours to about 1 hour, which is of great significance for further advancing the Western Development Strategy, helping rural revitalization in the old revolutionary base areas, accelerating the construction of the Baotou-Haikou High-Speed Railway corridor, further improving and optimizing the layout of the national high-speed railway network, and enhancing Shaanxi Province's locational advantages and its hub status in the national railway network.