切缝药包掏槽爆破研究与应用

切缝药包对爆炸能量具有极强的导向作用，将切缝药包引入到掏槽爆破，提出“先切后掏”的爆破思想。先采用切缝药包爆破将中心部分岩体与围岩分割开，克服爆炸初期自由面单一，围岩的夹制作用大等不利因素。在后续炮孔的爆炸作用下，将槽腔范围内岩体破碎，并抛掷出槽腔。进行了矩形切缝药包掏槽数值研究，结果表明：沿切缝方向能量得到了优先释放，沿切缝两炮孔中间的有效应力达到200 MPa以上，炮孔间裂纹形成贯穿。单独掏槽爆破炮孔利用率达到97.8%，全断面一次爆破平均炮眼利用率为96.9%，验证了切缝药包掏槽爆破的可行性。

Research and application of cut blasting with slotted charge

Slotted charge has significant guiding effect on blast energy.Slotted charge was introduced into cut blast,and the idea of "cut to drivage" was put forward.Divided a certain range of central rock part from the surrounding with slotted charge blast.This method avoids the disadvantage of single free surface and great clamping effect.Utilized the blast energy of following boreholes,break the rock and throw the fragment out of cavity.Perform numerical simulation of rectangular cut blast.The energy along kerfs’ direction is released in priority,and the peak value of point along kerfs is above 200 MPa,which forms the penetration of cracks.In separate cut blast,the utilization rate of borehole reaches to 97.8%.In full section blast,the average utilization rate of borehole reaches to 96.9%.Field tests validate the feasibility of cut blasting with slotted charge.