四川西昌至云南香格里拉高速主线首条隧道贯通

Core Points - The Sichuan Xichang to Yunnan Shangri-La Expressway (referred to as "Xichang Expressway") has achieved dual tunnel completion, marking the first tunnel to connect the main line of the expressway [1][3] - The Xichang Expressway is a key project under China's "14th Five-Year Plan" for transportation, serving as an important segment of the G7611 national expressway from Duyun to Shangri-La and connecting the provinces of Sichuan, Yunnan, and Guizhou [3] - The project, constructed by Shudao Group, spans a total length of 233.132 kilometers, with a main line of 155.49 kilometers, featuring three branches and designed for a speed of 80 km/h [3] - The expressway includes 32 tunnels and 131 bridges, with a bridge-tunnel ratio of 73.4%, and has an estimated total investment of 587.38 billion yuan [3] - The completion of the Xichang Expressway will end the historical lack of expressway access for Yanyuan and Muli counties in Liangshan Prefecture, significantly improving transportation conditions in ethnic minority areas and promoting high-quality economic and social development [4] Project Challenges - The construction of the Dunjia Ping Tunnel faced severe challenges due to its location in a strong seismic zone, steep terrain, and significant weathering at the tunnel entrance, leading to risks such as surface subsidence and instability [3] - The project team implemented real-time deformation monitoring and automated warning systems to ensure construction safety and quality, alongside strict safety and quality management protocols [3]