Study On Rules Of Water Inrush From Mining Steep Inclined Coal Seam On Confined Aquifer

The coal mine is all over the country,and the existing conditions of coal in the underground are different,and the steep coal seam(the coal seam with the inclined angle of the coal seam is greater than 45 degrees)is widely distributed,and with the expansion of the mining scale,more and more mines have begun to exploit the steep inclined coal layer,and many of them are in the bottom of the steep coal seam.Because of the threat of plate confined water,it is very important to study the mechanism of water inrush from the steeply inclined coal seam floor,which is very important for mining steep seam to prevent floor water bursting.Based on the combination of theoretical analysis and numerical simulation,the deformation and failure characteristics of the floor slab of the working face floor are caused by the joint action of the rock mass surrounding the roadway and the working face and the water pressure of the confined aquifer on the floor rock.The mechanism of water inrush is systematically studied,the research content and achievements are as follows:(1)analysis of mining pressure under the action of stope wall rock stress distribution,crack development,goaf bottom floor fracture zone depth,failure zone of coal wall in front of face;from along the seam inclination and along the seam to the two aspects of analysis of coal seam angle,the length of the working face and the working face advancing distance effect on the failure characteristic and water inrush in steep coal seam mining of the floor.(2)according to the inclined coal seam characteristics,by using FLAC3D numerical calculation software,the establishment of the confined aquifer in steep coal seam working face to longwall mining floor three-dimensional flow calculation model of solid coupling numerical simulation,analyzed coal seam inclination angle and different face width and working face advancing distance changes,along the tilt direction of coal seam and the coal seam floor rock stress,plastic zone and changes in the law.(3)according to the simulation results,the corresponding prevention measures are put forward to prevent the water inrush from the bottom of the steep seam in the confined aquifers.