Study On The Water-control Structures Of Deep Karst And Nonlinear Prediction Of Floor Water Inrush

After fourty years intensive mining,Yanzhou Mining Area has begun to plan and carry out the deep coal seam mining for the recoverable resources of coal seam NO.3 decreased sharply.The geostress and the groundwater pressure increase along with the incremental mining depth,and the risk of floor warter inrush is also increasing rapidly.The Ordovician limestone aquifer in Yanzhou Mining Area is rich in water and has a serious threat to the mining of the deep coal seam.It has great significance to study the water abundance of the Ordovician limestone aquifer and evaluate its influence on deep coal resources.The paper takes Yanzhou Mining Area,including Xinglongzhuang Coal Mine,Dongtan Coal Mine,Baodian Coal Mine,Nantun Coal Mine,Yangcun Coal Mine and Beisu Coal Mine as the study area.Based on a great number of drill data and dewatering test data,the water-control structures of Middle Ordovician limestone and a nonlinear model for predicting the water inrush from Ordovician limestone aquifer under the coal seam was established using the method of theoretical analysis,mathematical geology,numerical simulation,and machine learning.The water abundance and water-control structures of Ordovician limestone aquifer in Yanzhou Mining Area was studied by collecting and sorting out the drill data,curvature method,and fractional theory.A nonlinear model for predicting the water inrush from Ordovician limestone aquifer under the coal seam No.16 and No.17 was established by combining the advantage of AHP and LS-SVM considering eight factors,which are aquifer thickness,syncline capacity dimension,anticline capacity dimension,fault capacity dimension,curvature value,water pressure of the aquifer,unit inflow of drill,and permeability coefficient.According to the dewatering test data,a 3D groundwater numerical model of Ordovician limestone aquifer in Yanzhou Mining Area was built.The normal water inflows and the maximum water inflows were calculated using the groundwater model.The results of this study were intended to improve the interpretation of the watercontrol mechanism of deep geological structures and to provide a better understanding for the prevation of water inrush from the Ordovician limestone aquifer in Yanzhou Mining Area.