Study On Drillhole Pressure Relief Technology For Surrounding Rock Of High Stress Coal Roadway In Wuyang Coal Mine

With the increasing exploitation of coal resources,shallow coal seams and mines having simple geological conditions are gradually disappearing,the difficulty of mining is increasing.Especially high-stress coal roadway,roadway surrounding rock is difficult to control,the roadway support is difficult,and the supporting methods and supporting parameters are not designed properly.Insufficient or excessive support intensity have a great impact on roadway excavation and mine production,even affect the personal safety of mine workers.The 7609 transportation roadway of Wuyang coal mine as the engineering background,and comprehensively used the combined research methods of field investigation and data analysis,numerical simulation analysis,theoretical analysis and field measurement to relieve drilling pressure and control surrounding rock in high-stress coal seam roadway.The following results were mainly achieved:(1)Analyzing the general situation of 7609 transport roadway in Wuyang coal mine,which belongs to the roadway of high stress coal seam and is susceptible to the influence of dynamic pressure,analyzes the support scheme of 7709 transportation roadway,summarizes the unreasonable selection of supporting parameters and the problems existing in the support of dynamic pressure roadway.(2)The basic concept and distribution law of geostress are obtained by analyzing the principle of geostress;Based on the principle and method of ground stress test of sleeve fracturing method,3 # coal seam floor stress test and analysis were carried out.According to the results of lithology test and ground stress test,the design suggestion of roadway support of 3 # coal seam.(3)The stress distribution and deformation of surrounding rock of high stress coal roadway are studied.The influence of dynamic pressure coefficient on stress distribution,plastic zone distribution and deformation law of surrounding rock of high stress coal roadway is analyzed by FLAC3 D numerical simulation method.(4)According to the study of the principle of high stress relief drilling,the elasto-plastic analytical solution of stress and displacement of roadway surrounding rock under the plane strain model was revised.To control the volume expansion of roadway surrounding rock,the theoretical basis for the determination of pressure drilling parameters was preliminarily given.(5)Based on the numerical simulation of FLAC3 D,the influences of the length ofborehole pressure relief,diameter and spacing on the leading bearing pressure of roadway driving face,the stress and deformation of surrounding rock and the stress of bolt in roadway of high stress coal seam are analyzed respectively.(6)Based on the above research results,the designed borehole pressure relief technology of 7609 transport roadway in Wuyang coal mine is tested.The results of numerical simulation of stress distribution of surrounding rock,plastic zone and deformation monitoring of roadway surrounding rock show that,By using the technique of borehole pressure relief of surrounding rock in high stress coal roadway,the peak stress of roadway can be transferred to the deep,which can effectively control the deformation of surrounding rock and ensure the safety and stability of7609 transportation roadway.