Physical Simulation Study on Dynamic Monitoring of Water Inrush from Concealed Fault in Confined Water

In order to study the dynamic law of water inrush from floor crack expansion and hidden fault progressive uplift deeply, a fixed-point dynamic monitoring system for coal seam floor failure and progressive uplift coordinated water inrush was developed. The system consists of constant pressure pressurizing device, progressive uplift fixed-point quantitative observation device, uplift water quantitative acquisition device and stress detection system, which can directly realize the situation of coal seam floor failure and confined water progressive uplift at different positions of floor, and reveal the mechanism of collaborative water inrush from stope floor failure and progressive uplift and their temporal and spatial evolution law. The test results show that with the advancing of the working face, the progressive lifting process of hidden faults has experienced four stages: natural lifting stage, progressive lifting stage, enhanced lifting stage and penetration stage, which has an important relationship with the speed and scale of crack development of coal seam floor rock mass. When the peak value of mining stress unloading occurs, the progressive lifting degree is strengthened and the water volume increases, and the unloading degree of floor rock mass reaches the peak value synchronously with the progressive lifting intensity and the water output of dynamic monitoring pipe.