深埋煤层强采动覆岩破断特征及矿压显现规律OA

To further elucidate the manifestation pattern of strong strata behavior in overlying rocks under intense mining in deep-buried coal seams,this study takes the 1014 working face of Huangling No.1 Coal Mine as the engineering case study.Geological investigation,physical similarity modeling,and in-situ monitoring were jointly employed to analyze the fracture-instability characteristics of the overburden and the associated ground-pressure response.A pressure-relief scheme based on pre-splitting borehole roof cutting was then proposed,and its unloading and regulation performance was validated through field measurements.The results show that with continuous face advancement,both the roof caving interval and the shield support resistance increased progressively,and the support resistance reached a maximum of 34 MPa when the face advanced to 210 m.The spatial distribution and intensity characteristics of overburden microseismic events indicate that the thick and hard sandstone layer above the coal seam is the mechanical source that induces strong ground pressure manifestation on the working face and continuous large deformation of the gob-side entry.Field monitoring further demonstrates that,after pressure relief,the roadway roof subsidence,sidewall convergence,and floor heave decreased by 17.8%,25.4%,and 23.87%,respectively.The pre-splitting borehole roof-cutting pressure-relief scheme can effectively suppress strong ground-pressure behavior and mitigate roadway surrounding-rock deformation.The research findings provide a reference for the surrounding rock control of gob-side entry in mines under similar conditions.