CAJ | 학술논문

在近距离煤层群的下行开采中，上位煤层的回采直接影响到下位煤层开切眼围岩的应力分布、破坏规律以及围岩的运移规律，从而影响到切眼的支护方式。为了分析下位煤层工作面切眼锚杆支护的稳定周期，利用基于三维显式有限差分法的计算工具Flac3D，以矿井近距离煤层工作面10603的切眼支护为工程实例，对比分析了上位煤层开采后，切眼围岩在支护前和支护后的应力分布、破坏规律和运移规律。结果表明，切眼进行锚杆支护后，应力集中带及影响范围都减少了50％，围岩剪应力由支护前的2.5 MPa降低到支护后的0.6 MPa，围岩塑性区域比支护前减少了40％，有效地控制了围岩的破坏，且切眼顶底板稳定周期为26天，两帮稳定周期为28～30天。
재근거리매층군적하행개채중，상위매층적회채직접영향도하위매층개절안위암적응력분포、파배규률이급위암적운이규률，종이영향도절안적지호방식。위료분석하위매층공작면절안묘간지호적은정주기，이용기우삼유현식유한차분법적계산공구Flac3D，이광정근거리매층공작면10603적절안지호위공정실례，대비분석료상위매층개채후，절안위암재지호전화지호후적응력분포、파배규률화운이규률。결과표명，절안진행묘간지호후，응력집중대급영향범위도감소료50％，위암전응력유지호전적2.5 MPa강저도지호후적0.6 MPa，위암소성구역비지호전감소료40％，유효지공제료위암적파배，차절안정저판은정주기위26천，량방은정주기위28～30천。
In the downward mining of close distance coal seam group , the mining of upper coal seam directly affects the stress distribution , damage law and migration law of surrounding rock in lower coal seam , thereby affecting the support pattern of open-off cut .In order to analysis the stable period of open-off cut support in lower coal seam with anchor bolt support , by using the computing tools Flac 3D, which was based on three dimensional explicit finite difference method , and taking the 10603 working face in close coal seam as example , the stress distribution , dam-age law and migration law of open-off cut under support or not , with the upper coal seam has been mined , were comparatively analyzed .The results showed that after the open-off cut has been supported with anchor bolt , the stress concentration belt and its influence scope of surrounding rock are decreased by 50%, the shear stress of sur-rounding rock has down to 0.6 MPa from 2.5 MPa, the plastic area of surrounding rock reduces by more than 40%, the stable period of roof and floor is 26 days, and the stable period of sides is 28~30 days.