岩溶区库水渗漏涌入隧道的水动力过程模拟分析OA北大核心CSTPCD

[Objective]Tunnel construction causes disturbance to the geological environment,especially in the karst area,which may induce the leakage of high-level reservoirs and cause the influx of reservoir water into the tunnel.However,It is necessary to conduct dynamic analysis or simulation for this hydrodynamic process.[Methods]In this paper,a large amount of water gushing in the tunnel caused by the leakage of Dalanchi Reservoir during the construction of Chongqing Xiema Tunnel is selected as a case study.The ModelMuse software is used to establish a numerical model of groundwater flow.The Reservoir package of MODFLOW is used to represent the water level-reservoir capacity-leakage change process.The leakage channel was generalized to be a strong permeable belt with high hydraulic conductivity.The model parameters were automatically calibrated by the PEST inversion pro-gram.[Results]The result show that The fitting coefficient R2 between the simulated value and the measured value of tunnel wa-ter inflow reaches 0.886 6,and the fitting effect is good.The simulation realizes the abrupt inflow process.Both plane and cross-section of the groundwater flow field reflects the variation of the groundwater dynamics of the reservoir water leakage into the tun-nel,and also show the change trend of the reservoir water level falling first and then rising with the tunnel excavation and lining.The result of water balance analysis reflect the proportion of tunnel water inflow in reservoir water leakage.The reservoir recharge aquifer accounts for 60％of the total leakage,and the supply of strong seepage zone into the tunnel accounts for 30％of the total leakage.At the same time,the lag response of tunnel water inflow to reservoir water change is verified.[Conclusion]The nu-merical simulation can better reflect the process of reservoir water inrush into the tunnel,and provide reference for the prevention and control of tunnel water inrush under similar geological conditions.