A novel collaborative study of abnormal roof water inrush in coal seam mining based on strata separation and wing crack initiation
Engineering Failure Analysis, 142:106762, 2022.
Summary
This work combines a physical simulation and a fracture-mechanics model to investigate water inrush from roof-bed separation during coal mining. A laboratory model based on the Yushujing mine's 21805 working face tracks the formation of separation spaces, their accumulation of water, and the eventual release of that water under hydrostatic pressure. An analytical treatment of wing-crack initiation includes T-stress and covers both compression-shear and tension-shear fractures. It also incorporates overburden loading, water pressure, fracture geometry, and rock properties. The timing of water inrush in the laboratory agrees with the field observations, while the predicted crack directions agree with those observed after water injection. The results indicate that separation cavities develop over an extended period. Together, the experimental and theoretical analyses help explain the development of water-conducting fractures and support measures for preventing roof-water hazards.