作者：余明高；滕飞；褚廷湘；晁江坤；李品

第一作者单位：河南理工大学安全科学与工程学院

摘要：为了研究浅埋藏近距离煤层群重复采动下地表漏风对采空区煤自燃的影响,利用FLAC^3D数值模拟软件,对神东矿区补连塔矿回采不同阶段覆岩孔隙率的发育规律、塑性区分布以及覆岩垮落高度进行模拟分析。结果表明:（1）上煤层回采完毕后,覆岩裂隙发育呈“U”形分布,最大裂隙高度达130 m,尚未通达地表;下煤层回采完毕后,覆岩最大裂隙高度达162 m,贯通地表。（2）上煤层回采完毕后,覆岩在上煤层上方62 m处发生明显离层,离层区下方覆岩下沉高度1.75～4 m,离层区至上覆岩层下沉高度0.25～1 m;下煤层回采完毕后,离层区进一步发育,离层区下煤层采空区顶板垮落,上煤层采空区岩体进一步沉陷,最大下沉高度达7 m,离层区至上覆岩层下沉高度>1～2 m。（3）在回采同一阶段,同一高度覆岩孔隙率变化率两侧大于中部;下煤层的回采使上煤层覆岩孔隙进一步发育,孔隙率变化率明显增大。

Abstract：In order to study how the surface air leakage caused by repeated mining at shallow buried and contiguous coal seam group influence the spontaneous combustion of coal in goaf.Based on ShenDong mining area of western China,plastic zoned,porosity and displacement of overlying strata at different extraction stages,where caculated by FLAC^3D.The results show that:(1)maximun crack height is130 m after the mining of upper seam,the height do not connect the surface;maxinmm crack height has devoloped to 162 m and connected the surface after the mining of underlying seam.There is a‘U’shape of strata fracture distribution.(2)There is an separation area at around 62 m over upper coal face after the mining of upper coal face,the deflection of strata under separation area is 1.75～4 m,the deflection of strata above the separation area is 0.25～1 m.With the mining of undelying seam,the separation area and the deflection of the strata has further developed.(3)At the same stage of extraction,the porosity rate of both sides of strata is bigger than that of the middle of strata.The porosity of strata has further developed with the mining of undelying seam.

基金：国家自然科学基金资助项目(U1361205；51404090；51574111)；

关键词：重复采动;浅埋藏近距离煤层群;覆岩裂隙;孔隙率;

DOI：10.16186/j.cnki.1673-9787.2018.01.001

分类号：TD752.2