Multi‐Scale Evolution Mechanism of Water‐Conducting Fracture Zone in Deep‐Mining Hard Roof

This study addresses the significant discrepancies in traditional methods for predicting the height of water‐conducting fracture zones in deep‐mining hard roofs, which can lead to catastrophic water inrush events. The 110,504 working face of Banji Coal Mine was chosen as the research site to systematically investigate the development characteristics of these fracture zones through a combination of theoretical analysis, field measurements, and numerical simulations. A key stratum identification model was proposed, based on the temperature‐compensated elliptical stress arch theory, to better account for high ground temperatures in the overlying strata. The theoretical calculations predicted a water‐conducting fracture zone height of 61.32 m and a fracture zone height of 21.25 m. The development of the fracture zone exhibited a three‐stage evolution: a slow development stage, followed by a rapid expansion stage, and finally a stable penetration stage. The findings suggest that the fracture zone height is primarily governed by the fracturing of key strata within an ellipsoidal stress arch, with overburden failure influenced by mining‐induced stress concentration and the structural characteristics of the overlying rock. These results provide both theoretical insights and empirical data for improving predictions of water hazards and enhancing the stability of overburden in deep mining environments.