Recently, the single tube of the Muzuo Tunnel in the LJ17 section of the Jiumian Expressway, constructed by CCCC Road & Bridge Construction Co., Ltd., was successfully holed through. It is reported that this is not only the longest tunnel in the Pingwu section of the Jiumian Expressway, but also the first extra-long tunnel of over 6 kilometers to be holed through on the entire Jiumian Expressway, and is one of the controlling projects of the whole line.

Since the official commencement of construction of the LJ17 section of the Jiumian Expressway on February 1, 2018, all participating personnel have overcome various difficulties, fully carried forward the spirit of fearing no hardship and daring to strive, and strictly carried out construction in accordance with quality and standard requirements. After 1,203 days and nights of arduous struggle, the Muzuo Tunnel was holed through two months ahead of schedule, laying a solid foundation for realizing the full-line breakthrough of the Jiumian Expressway as soon as possible.

The Muzuo Tunnel is located in Muzuo Tibetan Township, Pingwu County, with a total length of 13,473 meters, including 6,744 meters for the right tube and 6,729 meters for the left tube. It is a separated extra-long tunnel, with surrounding rock grades of III, IV, and V, and is a typical mountainous highway tunnel. Due to the complex geological structure, high construction difficulty, high safety risks, large drainage volume for reverse-slope construction, and a minimum burial depth of 8 meters, the risks of collapse and roof fall during construction are very high.