On April 11, the Xiling Tunnel — the longest Class I high-risk tunnel and a key control project of the Xi’an-Shiyan High-speed Railway — was successfully bored through by China Railway Seventh Group under CREC, laying the groundwork for subsequent ballastless track construction.
Located in Shangzhou District of Shangluo City, Shaanxi Province, the Xiling Tunnel lies in the mid-low mountainous region of the Qinling Mountains. Its left and right lines measure 18.083 km and 18.032 km respectively. As a double-tube single-track tunnel, it was constructed using four inclined shafts and 20 working faces simultaneously, making the organization highly complex. The surrounding rock comprises mudstone, sandstone, quartz schist, quartzite, marble, and marlstone. It cuts through two fault zones, eight folds, and ten shallow sections, making the geological structure extremely complex and prone to water inrush, collapses, soft rock deformation, gas outbursts, and base uplift — all of which pose significant construction risks.
The Xi’an-Shiyan High-speed Railway is designed for speeds up to 350 km/h and spans a total length of 256.7 kilometers, with the Shaanxi section measuring 169 kilometers and including five stations: Xi’an East, Lantian, Shangluo West, Shanyang, and Manchuanguan. The segment undertaken by China Railway Seventh Group includes 20.26 kilometers of the pre-station engineering works.
