Abstract:
The construction of the Xiongdongwan tunnel on the Lanzhou-Chongqing railway was very risky because it passes through a soft and fractured coal measure strata, with the rock stratum containing goafs and gas. This paper analyzes the various risks concerning construction in a goaf, including gas bursts, mud bursts, water inflow, and deformation and collapsing of surrounding rock. It also addresses the measures to avoid these risks, including a review of the significant risk sources, advance geological forecasting, construction resource control, and management of the construction unit.