Study on electrical potential inversion imaging of abnormal stress in mining coal seam

During the mining activities, coal-rock dynamic disasters have caused grievous casualties and massive property losses. It is the severe problem for regional monitoring of abnormal stress. Electrical potential (EP) can be produced on coal rock under loading, and its response is related closely with the loading stress and damage evolution. Meanwhile, electric field inversion has the advantage to realize regionalization monitoring in the space. To identify the abnormal stress localization characteristics in mining coal seam, after theoretical derivation, the strategy of EP inversion imaging on is studied under bilateral model. Further, simulation experiment of coal rock under loading is conducted. The abnormal probability zones of sample can be identified with EP inversion imaging, while it corresponds with severe damage zones with significant crack propagation. It can be utilized to reveal the localized characteristics of damage and failure of coal rock spatially. Finally, the results of EP inversion in the mining coal seam indicate that the abnormal probability zones can be considered as stress concentration and dynamic hazard areas. Its effectiveness is verified by microseismic monitoring and rock-burst hazard assessment. The study provides a new idea to monitor abnormal stress zone regionally and forecast dynamic disasters in the field.