Bearing Stress Evolution Law of Normal Fault Under Two Different Mining Sequence

Taking the working face mining along both sides of the normal fault when working face is positioned along the positive fault, the FLAC^3D numerical simulation is used to study the stress of two plates coal pillar in fault and the evolution laws of advance support stress of replace working face when footwall working face replaces upper working face firstly or the upper working face replaces the footwall working face. Research results show that: mining is on one side of the working face near normal fault, the stress concentration degree of coal pillar of the footwall face mining is less than that on the upper plate, footwall face mining has bigger influence on the stress of coal and rock in upper plate; mining is on both sides of the working face near fault, when upper plate replaces the footwall face mining, the stress concentration degree of coal pillar of upper plate is higher; when footwall replaces the upper plate face mining, the stress concentration degree of coal pillar of footwall working face is lower; advanced support stress concentration of replace face is obvious under two kinds of mining order; the advanced stress concentration degree of upper plate working face is greater when upper plate working face replaces the footwall working face.