Numerical Simulation Of Mine Pressure Behavior And Support Resistance Of Fully Mechanized Mining Face With Large Mining Height

The mine pressure of large mining height fully mechanized mining face is affected by many factors.It is necessary to clarify the influence of different mining parameters on the high mining face and effectively control it.This is the basis for ensuring safe,efficient and economic mining of the working face.Determining the reasonable support intensity of the working face is the core task of the bracket selection of the working face.The calculation of the support strength of the support should be based on comprehensive consideration of various human and engineering parameters of the working face.This paper takes the 10103 coal face of No.10 coal seam of Yongning Coal Industry as the specific project and geological background,and establishes the calculation method of the reasonable working resistance of the hydraulic support,which is dominated by the instability and breakage of the key top layer of the working face;the method of numerical simulation is used.The influence of working face parameters on the behavior of underground pressure under the influence of working face parameters was studied.The falling height of the top face of the working face and the depth of the wall of the coal wall were analyzed.The falling height of the face of the working face under the influence of different parameters and the coal wall were established.Helping the depth of the fitting formula;using the amount of roof subsidence as the basis for determining the degree of mine pressure in the working face,established the fitting formula for the roof subsidence under the influence of different working face parameters;relying on the working face under the roof The amount of weight is determined by establishing the top panel control discrimination index of the working face,and the reasonable working resistance of the support is determined based on the index and the specific engineering and human parameters.(1)Based on the characteristics of mine pressure behavior in large mining height face,starting from the structure of the key layer directly above the working face,the calculation formula for the reasonable working resistance of the hydraulic support of the working face based on the direct top key layer is established,and the Yongning Coal Industry No.10 is calculated.The reasonable working resistance of the coal seam is 8048 kN.(2)The numerical simulation method was used to investigate the length effect of mine pressure in the fully mechanized coal mining face.It was found that the length of the working face increases,the peak bearing pressure ahead of the face increases,the peak position moves forward,the roof sinks,and the coal wall The depth of the fins and the falling height of the end face all show an increasing trend.(3)The numerical simulation method was used to study the mining angle effect of mine pressure in fully mechanized mining face.With the increase of mining face angle,the leading bearing pressure peak of working face was reduced and the peak position moved to the coal wall.The amount of roof subsidence decreases,the depth of coal wall kerfs,and the height of end-face fall are increasing.(4)The numerical simulation method was used to study the effect of different mining parameters on the mine pressure of the working face.It was considered that the factors affecting the mine pressure of the working face when the geological condition of the working face is certain are:the length of the working face,Mining angle,mining height,depth,hydraulic support support strength,end face distance and other factors.With the increase of working face height,the amount of roof subsidence,the depth of coal face in working face,and the height of end face of working face all show an increasing trend;with the increase of working face depth,the amount of roof subsidence in working face The depth of the ribs and the height of the end face of the coal wall all showed an increasing trend;with the increase of the supporting strength,the amount of roof subsidence,the depth of the coal wall kerf,and the height of the end face all showed a decreasing trend;along with the working face With the increase of end face distance,the depth of the coal wall of the working face and the falling height of the end face show an increasing trend.(5)According to the numerical simulation method,under the condition that the coal seam geological conditions are determined,summarizing the influence on the roof subsidence of each working face mainly includes:working face length,elevation mining angle,mining height,buried depth,and supporting strength.The formula for predicting the amount of roof subsidence available is:s = 292.6061nL-0.47503(?2 + ?)+14.669(H2 + H)+471.6571nM-322.187(P2 +P)-3565.237The formula for predicting coal wall gangs in the comprehensively available working face is:C = 0.007898L-0.893e0.06654? + 0.004722e0.2079H+1.2631nM-0.251771n P + 0.585N-9.704The formula for predicting the face falling face of the comprehensively available working face is:D = 0.0248L + 0.0145(?2 +?)+ 0.1009(H2 + H)+1.52E 5(M2+M)-7.052P + 1.342N-2.823...