On August 26, the Jiangjiashan Tunnel of Section XJZQ-2 of the Xiangyang-Jingmen Railway was successfully holed through after 546 days and nights of intensive work. With this, all four tunnels in the section have been safely and smoothly holed through with "zero accidents," laying a solid foundation for the subsequent main-line track laying and erection and the smooth advancement of the overall construction schedule.

The Jiangjiashan Tunnel is located in Leihe Town, Yicheng City, Hubei Province, and is a controlling, major and difficult project of the entire line. The tunnel is a single-tube double-track tunnel with a total length of 2,646.25 meters, designed for a speed of 350 km/h, and a maximum buried depth of approximately 241.09 meters. The geological conditions in the tunnel area are complex, with strong development of unfavorable geology and poor integrity of the surrounding rock. The tunnel passes multiple times through unfavorable geological conditions such as karst, faults and shallow cover, involving great technical difficulty in construction, many uncontrollable factors and high construction risk.

To ensure safe construction and controllable quality of the Jiangjiashan Tunnel, the project team dynamically optimized the construction organization and strictly controlled the safety step distance of tunnel construction. During construction, it strictly followed the principles of "emphasizing geology, managing advance, strict grouting, short advance, strong support, rapid closure, frequent monitoring and prompt feedback." In the face of complex geological conditions, it made full use of advanced geological forecasting and surrounding rock measurement techniques, conducted advance assessment, dynamically adjusted support parameters, controlled the convergence and deformation of the surrounding rock, and adapted to changes in the rock to prevent and control risks. It innovatively applied the construction technique of "micro-bench multifunctional trolley-assisted two-bench excavation method," earnestly carried out "process documentation," precisely optimized process times, effectively reduced cycle duration and fully improved construction efficiency. This not only ensured safety and quality but also minimized the impact of unfavorable geology on the schedule, ensuring the tunnel was holed through safely on schedule.

It is understood that the Xiangyang-Jingmen Railway is an important component of the Hohhot-Nanning High-Speed Railway, a main corridor of the "Eight Vertical and Eight Horizontal" high-speed railway network in the national medium- and long-term railway network plan. It is a major supporting project for building a "Hubei on Rails" and accelerating the construction of Xiangyang as a national railway hub city. After completion and opening to traffic, it will connect with the Jingmen-Jingzhou High-Speed Railway and the Yangtze River High-Speed Railway at Jingmen West Station, achieving one-hour travel between Xiangyang and Jingmen. It is of great significance for building a two-hour high-speed rail living circle in Hubei Province, improving the Yangtze River high-speed rail network, creating the Western Hubei ecological tourism circle and serving the high-quality development of the Yangtze River Economic Belt.