Fault-Induced Floor Water Inrush in Confined Aquifers under Mining Stress: Mechanisms and Prevention Technologies—A State-of-the-Art Review

With the depletion of shallow mineral resources, mining operations are extending to greater depths and larger scales, increasing the risk of water inrush disasters, particularly from confined aquifers intersected by faults. This paper reviews the current state of research on fault-induced water inrushes in mining faces, examining the damage characteristics and permeability of fractured floor rock, the mechanical behavior of faults under mining stress, and the mechanisms driving water inrush. Advances in prevention technologies, risk assessment, and prediction methods are also summarized. Research shows that damage evolution in fractured floor rock, coupled with fluid-solid interactions, provides the primary pathways for water inrush. Stress-seepage coupling in porous media plays a decisive role in determining inrush potential. Mining-induced stress redistribution can activate faults, with parameters such as dip angle and internal friction angle controlling stress evolution and slip. Critical triggers include the hydraulic connectivity among faults, aquifers, and mining-induced fracture networks, followed by hydraulic erosion. A multi-pronged prevention framework has been developed, integrating precise fault detection, targeted grouting for water sealing, drainage to reduce water pressure, optimized waterproof coal pillar design, and dynamic risk assessment and prediction. However, gaps remain in understanding multi-physical field coupling under deep mining conditions, establishing quantitative criteria for fault activation-induced water inrush, and refining control technologies. Future work should focus on multi-scale numerical simulations, advanced active control measures, and intelligent, integrated prevention systems to clarify the mechanisms of fault-induced water inrush and enhance theoretical and technical support for mine safety.