Study On Hydrogeological Characteristics And Development Height Of Water Diversion Fracture Zone In Guanzhuanghe Coal Mine

After coal seam mining,the bending settlement of the overlying strata deforms and destroys to form a water diversion fracture zone,which causes the old kiln water around the mine,the stagnant water in the goaf and the underground aquifer water to enter the working face as water filling sources,resulting in mine water damage.Therefore,the study on the development height of water diversion fracture zone plays a positive role in preventing mine water damage and ensuring the safe mining of confined underwater working face.Taking the hydrogeology of Guanzhuanghe Coal Mine as the research object,and on the basis of fully collecting mine geological data,this paper analyzes the hydrogeological characteristics of aquifer and aquifer and the hydraulic relationship between aquifers.The threat of coal seam mining fissures to the safe production of working face is summarized.Using the numerical simulation method,the three-dimensional geological model of coal seam is established by FLAC3D,with emphasis on the numerical simulation of 11302 working face,and the changing rules of plastic zone failure,vertical stress field and vertical displacement of overlying rock are analyzed with coal seam mining.It is considered that when the working face advances 300m,the rock strata are fully mined,and the development height of the water diversion fracture zone is the maximum.Based on the statistics of the development height data of 47 measured water-conducting fracture zones,the sequence of influencing factors of water-conducting fracture zones is determined by the method of grey correlation analysis.On the basis of eliminating the redundant samples in the predicted samples,the prediction model of the development height of the water-conducting fracture zone based on BP neural network is established by using MATLAB software,and the development height of the water-conducting fracture zone is predicted by using the BP neural network model with mature training and qualified accuracy.Based on the analysis of the geological situation and mining situation of the 11302 working face,the height of the water conducting fracture zone of the working face is calculated to be 39.4mcm/59.2m according to the relevant standards.based on this,the exploration borehole is designed and constructed in the working face.The development height of the water conducting fracture zone is 52.2mm2/53.7m and the crack-mining ratio is 15.4mm/17.3 by using the borehole flushing fluid leakage method.The development height of the water-conducting fracture zone measured in the field is well verified with the numerical simulation prediction results and the BP neural network prediction results.Finally,the factors affecting the water richness of aquifer are analyzed,and four factors such as aquifer thickness,core recovery rate,brittle-plastic rock thickness ratio and the number of interlayer of aquifer are selected as the evaluation index of aquifer water richness.based on the water-rich structure index,the evaluation model of aquifer water richness is constructed.The research results of this paper have a certain guiding significance for the safe mining of Guanzhuanghe Coal Mine and provide a scientific basis for the prevention and control of mine water disasters.