Feasibility Study On Grouting Transformation Of Loose Aquifer In 1010 Working Face Of Wugou Coal Mine

Mine water damage is an important factor that threatens the green and safe mining of coal mines,especially mining under thick loose aquifers,which is more likely to cause water bursting and sand bursting accidents,and thin bedrock coal seams under thick loose aquifers are widely distributed in China.The shallow coal resources in the first and third mining areas are very close to the fourth aquifer in the upper Loose Cenozoic,and the hydrogeological conditions are relatively complicated.The head pressure of the aquifer has risen to 1.5 MPa.The diversion fissure zone and collapse zone will be affected after mining.In the aquifer,water bursting and sand bursting accidents are extremely easy to occur.According to the"Details of Water Prevention and Control of Coal Mines",conventional water disaster prevention techniques and methods are adopted,and it is difficult to achieve safe and efficient mining of shallow coal seams.Therefore,the fourth aquifer is split,diffused,and permeable grouting reformed to change the internal runoff recharge conditions of the aquifer,reduce the permeability of the aquifer,and change the aquifer to the aquifer or equivalent aquifer.The safe and efficient mining of shallow coal resources in the remaining blocks of Wugou Coal Mine is necessary.The thesis takes the working faces of 1010-1,1010-2,and 1010-3 in Wugou Coal Mine as the research object.Based on a comprehensive review of domestic and foreign cutting-edge technologies for controlling water and disasters in coal seams near the aquifer,the geological,hydrological and geological data of the research area are collected.A pre-harvest hydrological exploration hole was designed,an aquifer and overlying rock samples were taken,an engineering geological model was constructed,and numerical analysis and technical,economic,and safety analysis and selection were performed,and the following results were obtained:1.The thickness of grouting aquifer sand layer in the study area is 17.10~29.10m,the lithology is complex,the particle composition is not uniform,the gradation is medium to good,the unit water inflow is 0.001717~0.08559L/s.m,and the permeability coefficient is 0.01129~0.3993m/d,Water-rich is weak.2."Four inclusions"directly cover the coal-bearing strata,and form a direct hydraulic connection with the sandstone fissure aquifer through weathered fissure zone.The distance between the grouting aquifer and the mining coal seam is 18.90~57.60m,and the overburden strength is weak~medium Hard type.3.Then based on the basic geological data,use FLAC~3DD software to establish a model to simulate the grouting diffusion,select the final grouting pressure of more than 10MPa and the grouting hole spacing of 45m to 50m,and the damage law of overlying rock movement during coal seam mining Through numerical simulation analysis,it was found that the changes in stress and displacement caused by the mining of the coal seam after the grouting transformation were smaller than those before the grouting transformation.Finally,the grouting scheme and grouting range were selected,the layout of grouting holes was designed,and the social and economic benefits were evaluated.It was found that the aquifer grouting reconstruction project has good social and economic benefits.