Abstract
<title>Abstract</title> <p>To address the problems of non-uniform stress distribution, severe local plastic failure, and insufficient adaptability of uniform support in roadway surrounding rock under the combined mining influence of the stopping-line coal pillar and goaf, the west-wing auxiliary haulage roadway beneath the 110501 working face of Banji Coal Mine was taken as the engineering background. The floor failure depth after working face mining, the stress evolution characteristics of the underlying strata, and the deformation and failure characteristics of the roadway surrounding rock were investigated using theoretical analysis, numerical simulation, and field monitoring. Based on these results, a zonal differentiated support optimization scheme was proposed.The results show that after mining of the 110501 working face, the plastic failure depth of the floor is approximately 22 m, and the failure zone presents a bowl-shaped distribution. The shallow floor is dominated by tensile failure, whereas the deep floor gradually transforms into shear-slip failure. The vertical stress beneath the stopping-line coal pillar exhibits an obvious depth-dependent attenuation characteristic. A pressure-relief zone is formed beneath the goaf, while a high-stress concentration zone develops near the stopping-line coal pillar side.Along the excavation direction, the surrounding rock of the west-wing auxiliary haulage roadway shows significant zonal characteristics. In the coal-pillar influence zone, the peak vertical stress on the two ribs reaches 30.53 MPa, with a stress concentration factor of 1.74. Plastic failure is mainly concentrated in the two ribs, shoulder corners, and floor corners. According to the failure characteristics of the surrounding rock in the high-stress zone, an optimized support scheme was proposed by increasing the density of rib bolts, adding additional rib bolts, optimizing the symmetrical arrangement of cables, and increasing the cable length.Numerical simulation and field monitoring results indicate that after support optimization, the stress distribution in the roadway surrounding rock becomes more uniform, and the extent of the plastic zone is significantly reduced. The final roof-to-floor convergence and rib-to-rib convergence are reduced by 29.78% and 27.36%, respectively. The roof separation at the shallow and deep monitoring points is reduced by 15.22% and 6.15%, respectively. The research results can provide a reference for surrounding rock stability control and differentiated support design of deep roadways affected by stopping-line coal pillars.</p>