穿越贺兰山铁路隧道贯通

Core Points - The successful completion of the Helan Mountain Tunnel marks a significant milestone for the Baoyin High-speed Railway's Yinba branch, which is part of China's "eight vertical and eight horizontal" high-speed rail network [1] - The Yinba branch spans approximately 111 kilometers, connecting Yinchuan in Ningxia to Alashan League in Inner Mongolia, with the Helan Mountain Tunnel being a critical engineering challenge [1] Summary by Sections - Tunnel Specifications: The Helan Mountain Tunnel is 8,792 meters long, located at the border of Alashan League and Yinchuan, and crosses a sensitive ecological area with complex geological conditions. The maximum burial depth exceeds 230 meters, and the construction faced high risks of water intrusion and collapse [1] - Construction Techniques: To minimize disturbance to the Ming Great Wall, the construction team employed a low-disturbance combination technique of "mechanical excavation + C6 drilling machine operation + dynamic monitoring," ensuring high-quality and efficient tunneling while protecting ancient heritage sites [1] - Economic Impact: Once operational, the Baoyin High-speed Railway's Yinba branch will enhance the railway network layout between Ningxia and Inner Mongolia, improve regional connectivity, and promote coordinated economic development along the route, injecting new momentum into high-quality regional economic and social development [1]