Research And Application Of Surrounding Rock Deformation And Control Technology Of Re-mining Face Passing The Abandoned Roadway

In this paper,based on the engineering background of recovering the coal pillars of the original main roadway in the 31521 working face of Daizhuang Shengjian coal mine,using the method of field investigation,theoretical analysis,numerical simulation and industrial test,the deformation and failure characteristics and control technology of surrounding rock when the stope passes through the Empty Roadway are studied.According to the actual mining conditions of 31521 working face,the method of passing through the goaf and the supporting scheme of the goaf are put forward,and the field industrial test and monitoring are carried out.The main research results are as follows:(1)Based on the field investigation of 31521 working face,the spatial position relationship between the abandoned roadway and the working face is determined;the relationship between the stability of surrounding rock of the abandoned roadway and the stability of coal pillar and roof is studied;the variation characteristics of the vertical stress of coal pillar and the influence of its stability on the working face are analyzed;and the main roof stability is analyzed by establishing the main roof mechanical model of the stope passing through the goaf The support resistance of the working face to ensure the stability of the roof is not less than 2.76MPa.(2)FLAC3D is used to establish a numerical model to simulate the deformation characteristics,stress distribution and plastic zone changes of surrounding rock of the abandoned roadway under the influence of mining when the abandoned roadway is not reinforced during mining.The results show that with the development of the working face,the coal pillar between the working face and the parallel abandoned roadway will lose its stability,and the surrounding rock of the abandoned roadway is seriously deformed,while the deformation of the surrounding rock of the vertical abandoned roadway is relatively small.(3)Based on the actual mining conditions of 31521 working face,the principle of classified control and segmented support is put forward for different types of abandoned roadway,and the method of combining wood crib,single prop and high water material filling support is adopted;the support scheme of the mining roadway is put forward,the reasonable support parameters are determined,and the support parameters at the intersection of the goaf and the mining roadway are optimized to improve the support strength of the surrounding rock and ensure the roadway Channel stability.(4)Through the field monitoring of the stress condition of the hydraulic support,the displacement of the surrounding rock of the vertical and mining roadways,and the deformation of the filling body of the parallel abandoned roadway in the 31521 working face,it can be seen that the mine pressure is normal,the deformation of the roadways and the filling body is small,and the supporting effect is good.After the application of this technology,the safe and efficient mining of the remaining coal has been realized.