Analysis of stress evolution characteristic of fault coal pillar in upper mining of deep working face

To study the stress evolution characteristic of fault coal pillar and determine the influence range of fault stress resistance, the stress of fault coal pillar, the stress evolution characteristics of fault coal pillar and the microseismic evolution characteristics were studied by theoretical analysis, numerical simulation and field monitoring. The results show that the range of plastic zone affected by advance abutment stress in the 2304 working face is 40.68 m. The fault tectonic stress is superimposed with the advance support stress of the working face, and an obvious stress concentration occurs at 40 m from the FL6 fault in 2304 working face. There is an obvious stress resistance phenomenon in the FL6 fault, and a stress-relaxed area of 6 m to 8 m near the FL6 fault in footwall coal seam. Induced energy blasting was carried out in the fault area, and small energy events were monitored near the FL6 fault during the induced energy period. The energy inside the FL6 fault was fully released. There was no large energy event during the mining of 2304 working face, and the induced energy blasting in fault areas and the pressure relief measures of large diameter drilling played a pre-pressure relief effect, which ensured the safe production of 2304 working face.