China Railway Construction Heavy Industry Group and China Railway 18th Bureau Group produce world's first large-slope spiral tunnel boring machine "Beishan No. 1". It can bores large gradients and small turns. A breakthrough in technology.

China Peoples Daily write world's first large-slove TBM will use construction of underground laboratory ramp in Beishan, China. The 10% slope slope is 7.2 kilometers long in clockwise spiral from ground down. 10% slope is 1 meter drop every 10 meter. Diameter 7.03 meter.

Xu Chunxian, construction head Beishan Underground Laboratory of the 18th Bureau of China Railway, the contractor say "This is first full-section hard rock boring machine for construction in such continuous large-slope, spiral small-turn tunnel."

http://hn.people.com.cn/BIG5/n2/2022/0905/c195194-40110771.html