高应力巷道围岩钻孔劈裂解危研究

Study on Splitting Relief of Borehole in Surrounding Rock of High-stress Roadway

针对目前岩爆解危措施存在的问题,提出在施工卸压孔的基础上通过液压机械对围岩实施劈裂实现解危的方法,开展了3种劈裂角度的卸压解危数值试验,试验再现了高应力巷道围岩钻孔劈裂损伤破裂演化全过程。结果表明,劈裂角度为0°时其钻孔顶底部的损伤破裂最明显,而劈裂角度为45°时其劈裂缝全长度范围内的损伤破裂最明显,二者的解危效果均较好,可避免能量的突然释放,实现岩爆解危;劈裂角度为90°时的钻孔劈裂解危效果不明显,劈裂角度从45°~90°,解危效果明显减弱;劈裂角度对围岩损伤破裂演化过程起主要控制作用,在钻卸压孔的基础上施工满足要求角度的劈裂缝,并结合围岩解危效果监测可更好地实现岩爆解危。

In view of the problems existing in the present measures of rock burst relief,on the basis of the construction of pressure relief hole,the method of splitting the surrounding rock through hydraulic machinery to realize the rock burst relief was proposed.And the numerical tests of pressure relief with three splitting angles were carried out.The experiments reproduced the whole process of splitting damage and fracture evolution of the surrounding rock in high-stress roadway.The results showed that the damage was the most obvious at the top and bottom of the pressure relief hole when the splitting angle was 0°,as well as in the whole length range of the splitting cracks when the splitting angle was 45°.These two kinds of situations both had a good effect on rock burst relief and can avoid the sudden release of energy and realize rock bust relief.The relief effect of borehole splitting was not obvious when the splitting angle was 90°.And the relief effect was obviously weakened when the splitting angle changed from 45°to 90°.The splitting angle played a major role in controlling the evolution of surrounding rock damage fracture.On the basis of drilling pressure relief hole,constructing splitting cracks,which met angle requirements,can better realize the rock bust relief by combining with monitoring the relief effect of surrounding rock.