In the mining of close coal seam, the stress concentration under the residual coal pillar in the upper coal seam leads to serious deformation to roadway surrounding rock in the lower coal seam. Hence, it poses a huge challenge to the maintenance of entry surrounding rock. Based on this, an approach of entry surrounding rock control technology, directional pre-splitting, and roof-cutting pressure relief, was applied. The stress and deformation of entry surrounding rock utilizing directional pre-splitting and roof-cutting pressure relief were studied by numerical simulation and field test The results indicated that the depth of stress concentration under the residual coal pillar achieve 44 m. With the application of the roof presplitting, the vertical stress of the entry roof decreased. Utilizing the roof presplitting with a height of 7 m and an angle of 15°, the gangue filled the goaf and supported the overlying strata. Meanwhile, the surrounding rock of entry was controlled with a constant resistance anchor cable (9 m length) and gangue prevention support structure. Through field test monitoring, the roof pressure and the deformation of surrounding rock increases rapidly at 30 ∼ 110 m behind the working face. From 110 ∼ 160 m, the increased rate of roof pressure and surrounding rock deformation gradually slows down and tends to be stable at 160 m behind the working face. The maximum displacement of the roof to the floor is 511 mm, and the maximum displacement of the gangue rock wall to coal wall is 421 mm. The remaining roadway meets the demand of the adjacent working face.

在密闭煤层开采中，上煤层残余煤柱下的应力集中导致下煤层巷道围岩变形严重。因此，对入口围岩的维护提出了巨大的挑战。在此基础上，应用了入口围岩控制技术、定向预裂、顶板切顶卸压技术。通过数值模拟和现场试验研究了定向预裂顶切卸压对入口围岩的应力和变形情况，结果表明残余煤柱下应力集中深度达到44 m。随着屋面预裂的应用，入口屋面的竖向应力减小。利用高度为 7 m、角度为 15° 的顶板预裂，矸石填满采空区并支撑上覆地层。同时，入口围岩采用等阻锚索（9m长）和防矸石支护结构进行控制。通过现场试验监测，工作面后30～110 m处顶板压力和围岩变形迅速增加。110～160 m处顶板压力和围岩变形增加速率逐渐减慢，在工作面后160 m处趋于稳定。顶板对底板的最大位移为511 mm，矸石岩壁对煤壁的最大位移为421 mm。剩余巷道满足相邻工作面的需求。脉石填满了采空区并支撑了上覆地层。同时，入口围岩采用等阻锚索（9m长）和防矸石支护结构进行控制。通过现场试验监测，工作面后30～110 m处顶板压力和围岩变形迅速增加。110～160 m处顶板压力和围岩变形增加速率逐渐减慢，在工作面后160 m处趋于稳定。顶板对底板的最大位移为511 mm，矸石岩壁对煤壁的最大位移为421 mm。剩余巷道满足相邻工作面的需求。脉石填满了采空区并支撑了上覆地层。同时，入口围岩采用等阻锚索（9m长）和防矸石支护结构进行控制。通过现场试验监测，工作面后30～110 m处顶板压力和围岩变形迅速增加。110～160 m处顶板压力和围岩变形增加速率逐渐减慢，在工作面后160 m处趋于稳定。顶板对底板的最大位移为511 mm，矸石岩壁对煤壁的最大位移为421 mm。剩余巷道满足相邻工作面的需求。入口围岩采用恒定阻力锚索（9 m 长）和防矸石支撑结构进行控制。通过现场试验监测，工作面后30～110 m处顶板压力和围岩变形迅速增加。110～160 m处顶板压力和围岩变形增加速率逐渐减慢，在工作面后160 m处趋于稳定。顶板对底板的最大位移为511 mm，矸石岩壁对煤壁的最大位移为421 mm。剩余巷道满足相邻工作面的需求。入口围岩采用恒定阻力锚索（9 m 长）和防矸石支撑结构进行控制。通过现场试验监测，工作面后30～110 m处顶板压力和围岩变形迅速增加。110～160 m处顶板压力和围岩变形增加速率逐渐减慢，在工作面后160 m处趋于稳定。顶板对底板的最大位移为511 mm，矸石岩壁对煤壁的最大位移为421 mm。剩余巷道满足相邻工作面的需求。顶板压力和围岩变形的增加速率逐渐减慢，在工作面后160 m处趋于稳定。顶板对底板的最大位移为511 mm，矸石岩壁对煤壁的最大位移为421 mm。剩余巷道满足相邻工作面的需求。顶板压力和围岩变形的增加速率逐渐减慢，在工作面后160 m处趋于稳定。顶板对底板的最大位移为511 mm，矸石岩壁对煤壁的最大位移为421 mm。剩余巷道满足相邻工作面的需求。