Research On The Rock Pressure Law Of The Working Face Passing Through The Fault Area Under Repeated Mining Of The Short-distance Coal Seam Group

This article to understand the repeated mining face crossing fault of mine pressure law,combined with the geological conditions of a mine in Guizhou,through theoretical analysis,laboratory simulation experiment,numerical simulation and field measurement and other research methods combined with the repeated mining face crossing fault layer GroundPressure of system research,discusses the technical measures working face crossing fault,in order to provide a reference for similar mine.Through theoretical analysis,combined with the mine geological data,discusses the feasibility of ascending mining,the use of "three zones" method,ratio analysis method,the surrounding rock obtained upstream repeated mining feasible.The mechanical properties of fault slip instability are analyzed.Simulation study on nearby repeated mining face crossing fault fissure and fault stress change and movement law of overburden similar experiments with laboratory Induced Rock greatly development of coal seam mining,the near fault fissure peak,far away from the fault rock compaction decreased gradually after.In the process of approaching mining fault,the fracture of the overlying rock increases with the distance from the fault,and reaches the peak near the fault.Compared with the single seam mining,the overburden fracture develops more fully and is more strongly affected by the fault.Fault plane normal stress and shear stress of single working face mining and repeated mining working face effects showed changes in different stress,repeated mining when the fault plane normal stress and shear stress were increased with the near fault working face far away from the fault after the normal stress and shear stress force decline and maintain a certain level.The roof collapse of repeated mining face shows a certain "time and space" effect.By using computer numerical simulation analysis of the single mining face crossing fault rock stress changes,fault plane normal stress and shear stress and repeated mining working face in different directions to promote the process of stress change,study shows that the overburden in single coal seam mining process of stress concentration with the working face and faults between close the rise in the face of the fault near the bottom stress concentration peak,face far away from the fault stress during mining gradually returned to normal level;the fault plane stress also increased with the working face close to the bottom,middle and top fault,normal stress and shear stress and some existing differences;repeat mining working face of upper and lower fault in different directions,the hanging wall of the fault stress is relatively lower mining stress greater stress on the working surface of the central fault disturbance more "sensitive",at the end of the fault plane Second,the fault plane is lagging behind the top.Field observation of repeated mining face crossing fault working face support resistance and coal wall length,the measured results show that near fault working face support resistance can be divided into "high" and "low","high pressure zone of coal wall length increased significantly,according to the characteristics of the fault zone face pressure the suggestions in this area should strengthen the equipment maintenance management,accelerate the speed of working face,strengthening roof reinforcement.