Stress-Release Technology and Engineering Application of Advanced Center Drifts in a Super-Deep Soft-Rock Tunnel: A Case Study of the Haba Snow Mountain Tunnel

In the construction of tunnels in the southwestern region of China, the super-deep burial depth results in extremely high ground stress. In the event of encountering soft rock, there is a potential risk of triggering severe deformation disasters, leading to issues such as support structure damage, project timeline delays, and a significant increase in costs. Therefore, there is an urgent need to propose an advanced stress-release technology to address the high-ground-stress issue caused by the super-deep burial in tunnels. The paper takes the Haba Snow Mountain Tunnel as an example and employs various methods such as numerical simulation and on-site monitoring to investigate the advanced stress-release technology of an advanced center drift in super-deep-buried soft-rock tunnels. It also determines the reasonable parameters for the advanced center drift. The research results indicate that setting the area of the advanced center drift to 60