The Baozuo Tunnel, the longest tunnel on the Sichuan section of the Xining-Chengdu Railway, was successfully broken through on July 25. The railway is constructed by China Railway No.2 Group Co., Ltd., a subsidiary of China Railway Group Limited.
The Baozuo Tunnel, located in Songpan County, Aba Tibetan and Qiang Autonomous Prefecture of Sichuan Province, stretches 11.795 kilometers. It sits at an average altitude of 3,500 meters, with its highest point reaching 3,693 meters.
The tunnel traverses an area with highly complex geological conditions, posing significant construction risks including tunnel collapse, mud and water inundation, and the emission of toxic and harmful gases. In addition, it is situated in an ecologically fragile area with an extremely adverse natural environment, posing tremendous challenges to the construction work. (....)