Investigation of the impacts of tunnel excavation on karst groundwater and dependent geo-environment using hydrological observation and numerical simulation: a case from karst anticline mountains of southeastern Sichuan Basin, China

Tunnel excavation has significant disturbance on groundwater system and related geo-environment, especially in karst regions like southwestern China. The present research was conducted to quantitatively understand the negative impacts posed by tunnel construction reveal behavior of under disturbance, with aid field survey, hydrogeological analysis, numerical simulation. results suggested that such as loss surface underground water, ground collapse, house deformation would be directly indirectly its dependent geo-environment result level drawdown excavation. degree range drainage impact were determined lithological characteristics strata. These dominantly distributed depressions valleys, direct ones occurred at first followed indirect ones. Simulation showed not occur synchronously spatial, but always around axis gradually expanded towards far away over time. maximum can reach approximately 25 m vertically 3000 horizontally for modeling tunnel. With numeral simulation, three response stages identified disturbance. practice water bodies eliminated since second stage, continue if existing failure waterproof until a new balance state achieved. improve understanding provide reference protection resources Chongqing worldwide.