The fracture development and distribution around the deep soft rock roadway are pivotal to any underground design. In this\npaper, both field investigation and numerical simulation were taken to study the fracture evolution and rock deformation of a coal\nmine roadway at Kouzidong mine, Fuyang, Anhui Province, China. Based on the borehole imaging technique, we found an\nasymmetric distribution of the fracture zone in the surrounding rock of the roadway. By analyzing the C value of the fractures in\nthe borehole images,we found that the fracture interval distribution of the surrounding rock of the tunnel, the number of fractures\nwill fluctuate decrease with the increase of the depth. To effectively study the fracture propagation and distribution of the roadway\nunder longwall retreatment and roadway excavation, the global-local numerical technique was applied via FLAC3D and PFC2D.\nIn the roadway excavation process, fractures were first formed in the shallow section of the roadway and progressively propagated\ntoward the deeper soft rock layer; the main failure mechanism was a tensile failure. During longwall retreatment, fractures\ncontinuously developed toward the deeper soft rock layer. However, the failure mechanism transformed to shear failure. From\nnumerical results, it can be seen that the stress concentration at the ribs was released, which led to shear failure at the roof and\nfloor. Due to the extensive tensile cracks in the shallow section, the surrounding rock experienced expansion and fracture. The\ndeep shear failure also induced the formation of the nonadjacent crushing zone and elastic zone, which is in line with the borehole\nimaging results.
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