However, extensive coal mining has left behind Goaf areas underground voids and fractured zones that pose serious safety hazards and environmental risks. These challenges require innovative approaches ...

However, extensive coal mining has left behind Goaf areas underground voids and fractured zones that pose serious safety hazards and environmental risks. These challenges require innovative approaches ...

(2) The special drilling structures, stepwise gradient pressurization, and segmented sequential downward grouting technique are proposed to ensure the grouting effect under goaf. (3) Finally, the ...

School of Emergency Management and Safety Engineering, North China University of Science and Technology, Tangshan, Hebei 063210, China Key Laboratory of Mining Development and Safety Technology, ...