Abstract：
To accurately predict the risk of water inrush during tunnel construction in karst mountain areas, the Huangmujian Tunnel on a railway under construction was selected as a case study. The spatial distribution characteristics of water abundance along the tunnel were analyzed through mutual validation of comprehensive geophysical interpretation and a water abundance index model. Based on this analysis, a multi-medium equivalent continuum model for the tunnel site area was established to perform refined dynamic simulation of water inflow, achieving an integrated qualitative and quantitative analysis of water inrush risks. The research results indicate: (1) The groundwater system at the Huangmujiank tunnel site is bounded by a nearly north-south watershed on the surface, with relatively independent hydraulic connections on the east and west sides. Tunnel excavation intercepts groundwater flow from recharge to valley discharge, with dense water table contours near the tunnel and a decreasing water level drop rate as the distance from the tunnel increases. (2) The water abundance along the tunnel exhibits strong heterogeneity,with high water-abundance zones primarily located at structural features such as faults and folds in the middle section of the tunnel. These high water-abundance zones account for 3.9% of the total tunnel length. (3) Hydrological parameter zoning and assignment in the model based on the water-abundance zoning results can avoid the subjectivity of parameter zoning and improve the accuracy of water inrush risk prediction. (4) The tunnel section from DK199+400 to DK199+760 is an extremely high-risk zone for water inrush. The water inflow volume decreases logarithmically over time, with a rapid initial decline in the water inflow per unit width, which then gradually stabilizes.
SHANG Haimin CUI Qingguo YU Jinqing WANG Qingang
.Risk Analysis of Water Inrush in a Tunnel Project in a Karst Mountain Area[J] MODERN TUNNELLING TECHNOLOGY, 2025,V62(1): 48-55
2025, Vol. 62 