【目的】解决工作面采用混凝土柔模充填技术沿空留巷后巷道稳定性问题。【方法】采用“柔模充填+聚能爆破预裂技术”。基于工作面顶板覆岩特征,综合运用理论分析和数值模拟的方法,结合现场施工条件,确定了切顶高度20.5m、切顶角度5°的深孔预裂爆破方案。【结果】研究结果表明,切顶后煤壁内弹塑性交界线内移,内应力场范围增大,高位砌体梁结构作用明显。随切顶高度的增加,充填体支护阻力和围岩变形量先减小后稳定;随切顶角度的增加,充填体支护阻力和围岩变形量不断增大。现场切顶施工后围岩变形量相比不切顶时顶底板移近量减少了56%,两帮移近量减少了72%,减少了后期维护成本,可为同类条件下煤矿切顶留巷提供经验参考。

【Purposes】 This article aims to solve the stability problem of the roadway after using  concrete flexible mold filling technology to leave the roadway along the goaf in the working face.To  solve the problem of roadway stability after retaining the roadway along the goaf, “flexible mold filling  + shaped charge blasting pre cracking technology” is adopted.【Methods】 On the basis of the charac⁃ teristics of the roof overlying rock of the working face, the method of theoretical analysis and numeri⁃ cal simulation, combined with the site construction conditions, is used to determine the deep hole pre- cracking blasting scheme with the cutting height of 20.5 m and the cutting angle of 5°.【Findings】The  results show that the elastic-plastic boundary in the coal wall moves in, the range of the internal stress  field increases, and the effect of the high masonry beam structure is obvious.With the increase of the  cutting height,the support resistance of the filling body and the deformation of the surrounding rock de⁃ crease first and then stabilize.With the increase of cutting angle, the support resistance of backfill and the  deformation of surrounding rock increase continuously.The deformation of the surrounding rock is re⁃ duced by 56% and the displacement of the roof and floor is reduced by 72%,which reduces the mainte⁃ nance cost in the later period and provides an empirical reference for the mining roof cutting and roadway  retention under similar conditions.