Study On Strata Behavior Regularity And Support Adaptability Of The First Mining Face In Shallow Buried Coal Seam In Huang Yuchuan Mine

4#coal seam of Huang Yuchuan coal mine is 150m in buried depth,the occurrence of rock pressure is more relaxed,and the roof breaking motion is not spread to the surface,which is distinct from the typical shallow coal seam in the process of mining.Therefore,to study the pressure appear below of initial mining working face,and to analysis the support adaptive,then,provides the basis for the mining of coal mining,the selection of the brackets and the layout of the work surface for the mine and similar geological conditions.The research combined the field investigation,laboratory test,theoretical analysis and numerical simulation with the determination of the working face through the overlying load calculation and the position of key stratum and breaking down,to get the key layer above the structure of Huang Yuchuan coal mine,to advance working face appeared in the process of shear stress and vertical stress,plastic zone distribution and caving step analyzed by using FLAC31)numerical simulation software,to get the working surface of the first weighting and periodic weighting distance;and finally the working face 11401 is made a practice and support adaptability.The research results show that there are two key layer structures above the coal seam in Huang Yuchuan coal mine.The main key layer is the middle sand rock layer of 22.37 m,which is 68.62 m thick from the coal seam roof.The subcritical layer is located at 8.56 m on the roof of the coal seam and is 21.51 m in the carbon shale layer.The initial pressure and the period of the main key layer are 23.87 m and 13.38 m respectively,while the initial pressure and period of the sub-critical layer are 37.62 m and 12.21 m respectively.FLAC30 numerical simulation shows that the first step of the working face is about 24m,and the cycle pressure step is about 8?12m.Finally,the 11401 working face was measured on the spot to get the first step of the working face is 19.8 m,the cycle pressure step distance is 9.72m,the maximum value of the pre support pressure is about 7.8m.The results of theoretical calculation,numerical simulation and field measurement are basically the same.During the production,the initial supporting force to meet the requirements of pressure,the safety valve opening rate is low,at the ends of the working face support resistance in a large amount of surplus,support selection is reasonable,which can meet the needs of the conditions of production safety.