Study On Stability Of Surrounding Rock And Filling Body Of Gob-Side Retaining Roadway In 12305 Working Face Of Yunjialing Mine

Series of underground disasters caused by coal pillar discharging have seriously threatened the safety of underground production.The technology of retaining roadway along goaf realizes a series of advantages,such as high recovery rate of mining area and continuous mining of working face.However,gob-side roadways have to undergo multiple mining effects,stress concentration,large deformation of surrounding rock,and roadway maintenance is difficult.Therefore,based on the research background of12305 transport roadway retaining,the stress-strain evolution of filling body and surrounding rock around high water roadway during retaining roadway stage is numerically simulated and analyzed by using the methods of theoretical calculation and analysis,numerical simulation and industrial practice;and the stress-strain of filling body near high water roadway during retaining roadway stage is calculated and analyzed by numerical simulation.Monitoring and analysis;monitoring and analysis of the development of cracks in roof strata of roadway in the first mining influence stage,retaining roadway stage and the second mining influence stage,monitoring and analysis of stress and strain in roadway surrounding rock.The main conclusions are as follows:(1)Filling body beside high water roadway has good bearing capacity in retaining roadway stage,which can effectively reduce the degree of deformation and destruction of roadway surrounding rock and meet the needs of roadway section.(2)The filling body provides a good supporting force for the upper and lower strata.Reinforcement anchor cables are adopted to reinforce the filling body.The filling body works together with roof caving strata and roadway side pillars to ensure its good triaxial stress state,greatly improving the stability of the filling body itself and the supporting effect of the roof is good.(3)Influenced by primary mining,the strata between 0 and 2 m in the shallow part of the overlying roof are the main influencing areas,and the length of bolts(cables)should be ensured in the design of roadway support;in the retaining roadway stage,the shallow strata of the overlying roof are more fractured,and the horizontal and vertical cracks intersect;in the second mining stage,the original cracks develop further,and the roof subsidence continues to increase.The influence range is 0-5 m,and the surrounding rock of roadway is seriously deformed and destroyed.