Aiming at protection scope of upper protective layer in adj acent coal seams,stress in protective layer after excavation was analyzed by using the FLAC3D numerical simulation,the protection effects of protective layer were worked out;according to the protection rules of stress-relief,the pressure-relief angles of protective layer in dip and strike directions were determined. The results showed that after upper protection layer extraction of adj acent coal seams,the upper and bottom pressure-relief angles in dip direction were respectively 67.7°and 63.5°and the pres-sure-relief angle in the strike direction was 47.7°. The pressure-relief angle calculated by the nu-merical simulation was close to that by the field investigation.%为了确定近距离煤层群上保护层开采保护范围，运用 FLAC3 D 数值模拟对保护层开挖后的应力进行分析，得出了保护层的保护效果；结合应力卸压保护准则，确定保护层沿走向和倾向的卸压角.结果表明，近距离煤层群上保护层开采后，倾向上卸压角为67.7°，下卸压角为63.5°，走向卸压角为47.7°.通过现场考察，数值模拟分析计算得出的卸压角接近现场考察的卸压角.
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