Compaction Response of Mining-Induced Rock Masses to Longwall Overburden Isolated Grouting

Surface subsidence in coal mine areas can cause serious geological hazards. After a seam is mined, the overlying rock layers fracture, collapse, and expand; fractured bulking masses are then continuously compacted under action of overburden load, which eventually leads to surface subsidence. Overburden isolated grout filling via boreholes, high-pressure grouting mining-induced fissures hard layer, uses pressure compact lower advance, replacing void effectively controlling The characteristics mass bulking, compaction associated with mining key design parameters control. In this paper, theoretical model masses’ compactness during injection proposed, determines filling. An experimental study was conducted reproduce evolution response results indicated that small no-pressure stage, low-pressure pressure-boost stages were generating effect It found substantially increased filled volume by transforming space into space. Using engineering measurement data, law for verified. This paper provides basis evaluation control effectiveness.