High stress is the main factor causing the large deformation of deep coal roadway. By borehole to transfe-ring stress and discharging pressure has become one of the main methods to control the stability of surrounding rock in the high stress area. Based on borehole pressure relief principle, and according to the background of practical projects, three pressure relieving hole layouts were designed, the effect on pressure relief of the three pressure relieving hole layouts was caculated and analyzed by numerical simulation method. The results showed: the pressure relieving hole layouts have great influence on the effect of pressure relief , by three row layout , the effect is most obvious; The discharging pressure circle appears around discharging pressure hole, the discharging pressure circle stack with each other, discharging pressure range increases; three row layout can not only make the peak stress transfer to deep, but also reduce the peak stress, which can effectively improve the surrounding rock stress environment. Discharging pressure hole produces pressure relief area it can provide certain deformation compensation space rnfor surrounding rock, and reducing the roadway deformation, by three row layout , tunnel deformation is minimum, compared with no discharging pressure hole, overall deformation of solid-coal side is reduced by 73. 9% , maximum settlement of roadway roof is reduced by 40% , the effect of deformation control is obvious.%高应力是造成深部煤巷大变形的主要因素.钻孔卸压已成为高应力区围岩稳定性控制的主要方法之一.基于钻孔卸压原理,以实际工程为背景,设计了三种卸压孔布置方式,并采用数值模拟的方法对不同卸压孔布置方式的卸压效果进行计算和对比分析.结果表明:卸压孔布置方式对卸压效果影响显著,卸压孔五花布置时,卸压效果最为明显；卸压孔周围形成卸压圈,卸压圈相互叠加,卸压范围增大；巷帮布置卸压孔使巷道周边形成的应力峰值向远离巷道的围岩深部移动,五花布置卸压孔时,不仅能够使应力峰值向深部转移,而且降低了应力峰值,有效改善围岩应力环境；卸压孔产生的卸压区,为巷道围岩提供给了一定的变形补偿空间,减小了巷道变形,卸压孔五花布置时,巷道变形最小,与无卸压孔时相比,巷道实体煤帮整体变形量减小了73.9％,顶板最大沉降量减小了40％,控制变形效果明显.
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