Water-rich Zone And Control Method Of Water Inflow From Working Face In Typical Arid And Semi-arid Mining Area

The prevention and treatment of mine water has always been the top priority of safe and efficient coal mining.Therefore,it is necessary to evaluate the water richness of the mining area,and then predict the water influx during the mining of the working face to ensure the safe production of the mining area.This paper takes Zaoquan coal mine as the research object,comprehensively uses on-site investigation,laboratory experiment,numerical simulation and other methods,combined with GMS,Arc GIS,FLAC and other software to predict and evaluate the water richness and water inrush risk of the mining area.,Proposed Zaoquan coal mining layout optimization plan;explored the evolution of groundwater flow field and the change of working face water inflow under different water-rich zones and different mining methods,and carried out the application of working face water inflow control in 130203 working face.The main research work and results of this paper are as follows:(1)The hydrogeological characteristics of Zaoquan coal mine were investigated and analyzed.Based on 327 borehole data,13 strata were divided according to the aquifer-containing layer,and a three-dimensional visualization geological structure model of Zaoquan coal mine was established.The model shows that the overall fold structure of each layer is obvious,the anticline axis dips from north to south,the stratum undulates at the boundary of the mining area,and the coal seams are missing in the central and northern areas of the mining area.(2)Using the analytic hierarchy process and the entropy method to determine the water-rich zone of Zaoquan coal mine into five categories:weak,weaker,medium,stronger and strong;based on theoretical calculations and numerical simulations,the development height of the water-conducting fracture zone is obtained,Identified the four types of danger zones as safety,early warning,danger and very dangerous;and on this basis,proposed the control methods of face water inflow of pre-harvest layout design,mid-harvest reorganization and control,and post-harvest continuous control.(3)Using GMS to establish a three-dimensional hydrogeological model,it was verified that the initial water flow field in the mining area flows from south to north,and the positive correlation between the water inflow of the working face and the enhancement of water richness was obtained,but the change was not significant;the mining method of the working face has a positive effect on the working face.The water inflow has a greater impact,which is due to the difference in water inflow due to the different development heights of the water-conducting fracture zone under different mining methods.(4)Analyzed the 130203 working face case,using the water-rich zone and water inflow prediction to get the theoretical value of 60m~3/h of water inflow during mining of the working face,and the numerical simulation is 88m3/h,which is close to the field measured value of 60?105m~3/h;Transient electromagnetic field measurements show that the source of water gushing at the working face is the fourth aquifer water,and it is speculated that the water-conducting fracture zone has not developed to the third aquifer,which verifies the accuracy of the prediction and the rationality of the working face layout.There are 44 figures,21 tables,and 96 references in this paper...