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Abstract In order to investigate the influence of the fault zone in the recovery, a water risk evaluation was carried out with FLAC3D software, mainly focusing on the evolution law of vertical stress in the bottom plate and the changing law of fracture in the bottom plate during different recovery stages. The study showed that the existence of the fault zone led to the increasing stress concentration in front of the working face, and finally reached the bearing limit of the bottom to produce fissures, which were further expanded by the action of mining stress and pressurized water, leading to the pressurized water gushing into the working face. The method of grouting was used to transform the bottom slab, with 12 drilling sites, 36 boreholes and 7 900 m3 of grouting, and the amount of water gushing after the transformation was 0.2 ~ 8 m3/h, which met the requirements of safe production.
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