Study on Dynamic Failure and Support Control of a Roadway Under Mining-Induced Seismic Loading Using a UDEC-Trigon Model

Dynamic failure of roadways subjected to mining-induced seismicity poses a major challenge to support design and coal burst control in deep coal mines. Using the roadway of the 3102 working face at M Coal Mine in Inner Mongolia, China, as the engineering background, a UDEC-Trigon model was established to compare four support schemes: unsupported, bolt support, combined bolt and cable support, and combined support with bolts, cables, and hydraulic props. The results show that support configuration significantly affects roadway deformation, particle velocity, stress redistribution, and fracture development. Bolt support alone provides limited improvement, whereas the introduction of cables markedly reduces rib deformation, high-velocity ejection zones, and fracture propagation. The maximum left- and right rib displacements decrease from 0.75 and 0.65 m under the unsupported condition to 0.12 and 0.25 m under combined bolt and cable support, respectively. Tensile cracks are more widely distributed than shear cracks, with tensile failure dominating the shallow surrounding rock and shear failure occurring mainly in deeper zones. Fractal analysis further indicates that combined bolt and cable support effectively suppresses crack development and reduces fracture network complexity, whereas hydraulic props provide only limited additional improvement. Based on the numerical results, an optimized bolt and cable reinforcement scheme combined with roof pre-splitting blasting was implemented in the field. The maximum deformations of the roof, ribs, and bottom were reduced by 40.0%, 60.0%, and 55.6%, respectively. These findings provide a reference for support design and coal burst mitigation in deep coal roadways.