Asymmetric Damage Mechanisms and Prevention Technology in Large-Section Gob-Side Entry Retaining

Based on the deformation and damage characteristics of surrounding rock in a large-section gob-side entry retaining combined with field observations an analysis dominant factors, overall control plan is formulated. The mainly includes structure high strength, stiffness ductility for roadside support; reinforcement roadway-in setup hydraulic fracturing pressure release mechanism advanced long, horizontal borehole “fracturing-jet” relief technology. Industrial tests were completed taking Tangan coal mine as engineering background. research shows that has typical “asymmetric” characteristics, including top sinking along inner side support, whole support skewing, even splitting damage; floor heaving; coal-side bolt basically losing ability bulging out from side. factors are disintegration mudstone by water deflection under stress, concrete asymmetric load, expansion due to insufficient strength strong dynamic roof, mutual influence relief. industrial test scheme optimizes stress environment space, effect remarkable, fully meets reuse requirements.