Recently, Ganzi Prefecture’s ultra-cold altitude long tunnel undertaken by JSTI GROUP has entered preliminary design consultation and research stage. In order to ensure the smooth development of the project and the improvement of technology, the best solutions come out, they organized an in-depth investigation and exchange on the applicability of TBM equipment for ultra-long tunnel in high cold and high altitude area.

Ganzi State Highway 549, Jiushi Road, Dakazishan Tunnel, 3500m above sea level, and 10.1km in total length. A difficult challenge of water and drainage protection, mechanical equipment efficiency, freeze-thaw and frost heave during construction and construction.