Mechanism and Control of Water–Rock Coupling-Induced Disaster when Mining below the Unconsolidated Confined Aquifer

Theoretical analysis and numerical simulation were conducted to study the disaster-causing mechanism of structural instability overlying strata induced by water–rock coupling effectively prevent control powered support jammed accident during mining below unconsolidated confined aquifer. The influencing factors on stability structure analyzed, method aquifer was designed. evolution process stress–displacement–crack field discovered. Meanwhile, prevention measures for proposed verified in some engineering practice. Results show that reduces with increase hydraulic pressure, breaking interval main roof, decrease strength waterproof coal pillar height. keeps a stable equilibrium state before fracture planes through whole coal–rock pillar. When pressure is small or bedrock surface thick topsoil layer, sliding block limit while because action unloading an movement. high, remains constant at about intact shear fall occurs as result weight block, which may accident. However, this type can be prevented drainage decreasing presplitting blasting hard grouting reinforcement, increasing height