https://www.youtube.com/watch?v=qCaVn71drYw

Peoples Daily informs Yuelongmen Tunnel, control project of Chenglan Railway finish after ten years construction. It happen 25 April. Chenglan Railway has 71 km tunnels and Yuelongmen Tunnel is one of 3 tunnels longer than 20 km. 

Tunnel in in Gaochuan area, Anzhou District, Mianyang City, Sichuan Province, and Tumen area, Maoxian County, Aba Tibetan and Qiang Autonomous Prefecture.

Tunnel location in earthquake fault zones, fault fracture zones, large deformation soft rocks.CRCC Chinese tunnel experts research. CRCC experts develop doctrine "active control of large deformation". They use non-explosive excavation, rock mass reinforce in advance and other methods.

It open traffic in 2023.

http://finance.people.com.cn/BIG5/n1/2022/0426/c1004-32409415.html