为获取双重上保护层重叠采动作用下被保护层卸压效应及保护层间的相互影响，以平煤八矿一采区为工程背景，采用数值模拟研究了丁、戊组煤层多工作面重叠开采应力分布规律。研究结果表明，丁组单一工作面保护己组煤层时，工作面边界煤柱最大应力值19MPa，影响范围达到下方80m，最大卸压值1MPa。丁组多工作面保护己组煤层时，多工作面间区段煤柱最大应力值达39MPa，向底板传递范围仅26m，最大卸压值为2.0MPa。丁组、戊组煤层多工作面重叠开采，工作面及煤柱错位布置时，区段煤柱应力集中减弱利于卸压，区段煤柱应力值由39MPa卸载至10MPa，己组煤层最大卸压值为6.5MPa。戊组单一工作面保护己组煤层最大卸压值为4MPa。双重上保护层开采能够增强卸压效应降低区段煤柱集中应力影响，基于得到的应力分布规律，划定了己组煤层的卸压范围，制定了己组煤层工作面采掘方案及预抽钻孔布置方案。

In order to obtain the pressure relief effect of the protected layer under double upper protective layer superposition mining，and the interaction between protective layers. Taking the No. 1 mining area of Pingmei No. 8 coal mine as the engineering background, numerical simulation is used to study the stress distribution law of superposition mining of Ding and Wu coal seams with multiple working faces. The research results show that, when only a single working face of Group Ding is mined to protect the Ji coal seam, stress concentration value of coal pillars at the working face boundary is about 19MPa, the influence range reaches 80m below, the maximum pressure relief value is about 1MPa. When the Group Ding multi-faces protect the Group Ji, the maximum stress value of the sectional coal pillars of Group Ding reaches 39MPa, but the transmission range to the bottom plate is only 26m, the maximum pressure relief value is 2.0MPa. When Group Ding and Group Wu coal seams are overlapped mining with multiple working faces, and the working face and coal pillar are staggered, the stress concentration weakening of the sectional coal pillars, and it is conducive to pressure relief. The stress value of sectional coal pillars is unloaded from 39 MPa to 10 MPa, and the maximum pressure relief value of Group Ji is 6.5 MPa. When a single working face of Group Wu protects the coal seam of Group Ji, the maximum pressure relief value of Group Ji is 4MPa. The double upper protective layer mining can enhance the pressure relief effect and reduce the concentrated stress of the sectional coal pillars. The pressure relief range of the Group Ji has been delineated based on the obtained stress distribution law, and formulated the mining scheme and pre pumping borehole layout scheme of the Ji coal seam working face.

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国家自然科学基金项目（青年基金）52004118;辽宁省教育厅青年科技人才“育苗”资助项目LJ2020QNL009;辽宁工程技术大学学科创新团队项目LNTU20TD-05