Study On Rock Pressure Law Of Impact Coal Seam Working Face In Zhangshuanglou Coal Mine

With the gradual increase of coal seam mining depth,worse mining conditions,and more intense mine pressure manifestation,especially under the condition of impact coal seam,it is easy to cause relatively large mine pressure accidents.Frequent occurrence of mine pressure manifestation accidents has brought serious harm to mine production and workers'safety.In 2010,Zhangshuanglou Coal Mine had underground pressure disasters,which caused many deaths.Therefore,it is particularly important to monitor the underground pressure of the working face under mining.This paper takes 94101 working face of Zhangshuanglou Mine as the research background,through the field measurement of the strata pressure appearing in the pushing stage of the working face,determines the strata pressure appearing law of the working face,and obtains the movement law of the roof and the dynamic and static load changing characteristics of the surrounding rock through theoretical analysis,which provides effective reference and technical support for the follow-up mining of the working face or mine mining under similar geological conditions.The roof structure of stope is determined through calculation and the roof structure model is constructed.The direct roof thickness of the model is 12.37m,the basic roof thickness is 17.4m,the mining height is 3m,and the top 4.19m above the basic roof is the 7 coal goaf.7.Elastic energy release after coal mining.9.Coal mining will not lead to the rapid and large release of elastic energy of broken roof in goaf again.The analysis of dynamic load mainly comes from basic roof fracture.After the data analysis of the two monitoring systems,the range and degree of stress and separation changes are basically the same.The obvious area of stress and separation changes mainly occurs at about 100 meters away from the working face,i.e.the static load changes obviously;the violent area of stress and separation changes mainly occurs in the range of 30 meters in front of the working face,i.e.the static load changes dramatically.The first weighting step of roof is 32.5 m and the periodic weighting step is 14.9 m after the analysis of the working resistance of the support.Based on the deduction and analysis of the daily release energy curve of microseism,it is inferred that the first weighting step of roof is 36.8 m and the periodic weighting step is 14.8 m,which is basically consistent with the measured weighting step of the support.It can also be concluded that the dynamic load of induced rock burst mainly comes from the basic roof fracture,which is consistent with the previous theory.The results of the analysis are mutually corroborated.Finally,numerical simulation is used to simulate and analyze the vertical stress,vertical displacement,plastic zone distribution and energy distribution along the strike direction of the stope in the mining process.According to the analysis,the simulation results are basically consistent with the field measurement results.