Research on the statistical damage model for advance abutment pressure distribution and the evolution of mining-induced stress in deep coal mining

This study addresses the unclear distribution characteristics of advance abutment pressure and mining-induced stress evolution during deep coal mining. A theoretical model for advance abutment pressure was established by coupling the statistical damage constitutive relationship of coal-rock mass with roof displacement and horizontal stress evolution. The model incorporates the Weibull distribution, Mises strength criterion, strain equivalence principle, and an attenuation parameter to characterize the progressive damage behavior of coal-rock mass under mining disturbance. Parametric sensitivity analysis was conducted to evaluate the effects of Young’s modulus, Poisson’s ratio, mining height, and roof displacement parameters on the peak value and location of advance abutment pressure. A three-dimensional numerical model of Working Face 8301 in Chenmanzhuang Coal Mine was developed using Rhino and FLAC3D to investigate mining-induced stress evolution. Results indicate that the stress field evolves from the initial in-situ state to a pattern characterized by “goaf unloading–roof adjustment–stress concentration ahead of the face”. The advance abutment pressure exhibits a typical trend of rapid increase, peak development, and decay. The theoretical model predicts a peak stress of 44.80 MPa at 16.17 m ahead of the coal wall, while numerical simulations yield peak stresses of 42–48 MPa at distances of 5–17.5 m. The close agreement between theoretical and numerical results demonstrates that the proposed model can reasonably characterize advance abutment pressure distribution and mining-induced stress evolution under deep mining conditions, providing a theoretical basis for support design, mining safety assessment, and disaster prevention in deep coal mines.