Study On Prediction Model And Numerical Simulation On Fissured Rock Seepage Of Chengchao Iron Mine

Due to years of caving mining and groundwater drainage, the original hydrogeologicconditions of Chengchao Iron Mine have been changed dramatically. Precipitation can rechargepit water rapidly and directly through the overburden broken rock mass in the mining area,which constitutes significant hidden danger of mining production. Based on GIS spatialanalysis principle, catchment analysis of mining area has been conducted to calculate thecatchment area of displacement zone and collapse pit accurately. A new pit water monitoringdevice has been designed successfully to realize accurate measurement of the pit water. Usingstatistical theory, the response relationship between precipitation and pit water has beenanalysised, and the infiltration coefficient of overburden rock mass in different condition ofprecipitation in mining area as well as the lag time of pit water to precipitation could beobtained. This paper built a kind of grey-transfer function coupling prediction model ofprecipitation recharge pit water for the first time, not only to overcome the deficiency offluctuation in GM(1,1) model, but also to make up for the defects of exponential growth in thetransfer function model, which resulted in higher accurate prediction of pit water. On the basisof building a generalized hydrogeological model of Chengchao Iron Mine, the Darcy-Brinkmancoupling seepage mathematical model was introduced to the prediction of the pit water ofChengchao Iron Mine, which could provide a reasonable mathematical model to thegroundwater seepage numerical simulation in the mines with overburden broken rock massresulted from caving mining. Based on finite element simulation, in which boundary conditionshave been built according to the results of catchment analysis and infiltration analysis and lagtime served as priority information, the permeability coefficient of overburden broken rockmass in Chengchao Iron Mine has been inverted. As a result, the seepage characteristics of rockmass in Chengchao Iron Mine has been studied, and the pit water under different precipitationintensity has been predicted. Research results have been supplied in developing pit water saftymeasurement of Chengchao Iron Mine, which could provid surface impermeable andunderground water preventing with theoretical basis applied technology.