Research on the deformation characteristics and effects of a single crack in roadway roof

Abstract In order to reveal the influence of crack occurrence on the deformation of roadway roof, a single crack model of roadway roof was established using the interface element in FLAC3D under different crack dip angles and connectivity ratio. The deformation and separation characteristics of roadway roof were analyzed. The results indicate that there is a certain similarity in the influence of the geometric shape of cracks on their own deformation and the displacement of the roadway roof. The connectivity ratio of cracks affects the distribution characteristics of symmetry and asymmetry in the peak displacement area of the roadway roof. The separation of the roadway roof may only occur when the cracks are connected and the inclination angle is large, and the degree of bedding shear sliding is not significantly affected by the inclination angle of the cracks. It can be seen that the asymmetric shape of cracks is another important reason for the formation of asymmetric deformation of the roadway roof.