渝昆高铁华山松隧道贯通 云南段仅剩最后一座隧道未通

Core Viewpoint - The Huashansong Tunnel, a key project of the Yukun High-speed Railway, has successfully completed its construction after over 1500 days of challenging work, with only one tunnel remaining to be completed in the Yunnan section of the railway [1][3] Group 1: Project Details - The Huashansong Tunnel is located in the Yunnan Province, with a total length of 16.4 kilometers, classified as a level I high-risk tunnel and the second longest single-hole double-track tunnel along the Yukun High-speed Railway [1][3] - The geological conditions of the tunnel are extremely complex, with nearly 90% of the surrounding rock classified as level IV and V, and it traverses 23 fault lines and areas with developed karst features, posing significant construction challenges [1] Group 2: Construction Techniques - The construction team utilized advanced techniques such as advanced horizontal drilling, deepening blast holes, and transient electromagnetic methods for precise geological detection, allowing them to anticipate geological changes [3] - A combined construction approach of "circular excavation, reserved core soil, and staged support" was adopted, along with surrounding radial grouting and advanced small conduit + pipe shed techniques to successfully overcome challenges related to surrounding rock instability [3] Group 3: Project Progress - The overall construction of the Yukun High-speed Railway has entered a critical phase, with an average of 11,000 construction personnel and 1,300 large machinery units deployed daily to expedite tunnel engineering, ballastless track, and post-station construction [3] - The Yukun High-speed Railway spans approximately 700 kilometers, with the Yunnan section measuring 388.6 kilometers, marking the first high-speed railway in Yunnan with a speed of 350 kilometers per hour, significantly reducing travel time between Chongqing and Kunming upon completion [3]