DOI: 10.11799/ce202511011
Stability study of remaining coal pillars in underground room-and-pillar goaf under over-gob mining in shallow buried thin coal seams
GAO Linjun
CHENG Wencong
Abstract：To clarify the dynamic stability evolution mechanism of remaining coal pillars in underlying room-and-pillar goafs under the disturbance of over-gob mining,we took the over-gob mining of the shallow buried thin coal seam in Sandaogou Mine as an engineering case.A comprehensive approach integrating theoretical analysis and numerical simulation was employed to systematically investigate the deviatoric stress field evolution and plastic zone expansion characteristics of the remaining coal pillars under over-gob mining.The research results show that the safety factor of the coal pillars remained from the room-and-pillar mining in the 5-2 coal seam reaches 1.541,indicating a feature of long-term stability.The spatial distribution of failure characteristics in the remaining coal pillars of the 5-2 coal seam exhibits an"O"shape,with the stability of pillars in the central area of the goaf significantly inferior to those in the boundary areas.The instability of central pillars is likely to induce overall instability of the pillar group.The distribution of the deviatoric stress field and the expansion of the plastic zone in the remaining coal pillars are primarily governed by the mining parameters.Moreover,the larger the room-and-pillar mining dimensions in the 5-2 coal seam,the more significant the disturbance effect from the over-gob mining in the 4-4 coal seam on the stability of the remaining pillars.
Keywords：over-gob miningcoal pillar stabilitydeviatoric stress distributionplastic zonesafety factorshallow buried thin coal seam
Publication Date：2025-11-20
Online Publishing Date：2026-01-15(First online date of this platform, not the publication date of the document)
Pages：7( 82-88 )