露天煤矿抛掷爆破参数分析

露天矿采用抛掷爆破技术，可将大量剥离物抛入采空区，使拉斗铲剥离量大为减少，剥离成本大幅度降低．抛掷爆破参数直接影响抛掷爆破效果．对露天矿抛掷爆破技术的发展、倒堆剥离台阶开采参数与抛掷爆破效果的内在联系、预裂爆破及倾斜钻孔的应用、排间延时及孔间延时的作用进行了分析与论述，详细介绍了采用理论结合经验公式的常规计算方法与D’Appolonia“图解法”模型确定抛掷爆破参数的过程及优化方法．结果表明，合理确定炮孔排间及孔间的起爆延时时间，可以大大降低爆破震动；采用超低密度炸药或不耦合装药可以取得较好的预裂爆破效果．

Analysis of Casting Blast Parameters in Surface Coal Mines

By using the casting blast technique in surface mines,a large volume of overburden will be thrown into the mined-out area,making the stripping volume of dragline operation be decreased and the stripping cost lowered.The casting blast parameters have a direct influence on the thrown result.Some techniques such as the development of casting blast technique in surface mines,the inherent relationship between the stripping bench parameters and casting blast effect,the application of pre-splitting blast and inclined drilling,the function of millisecond delay blast between drill holes and lines are introduced and discussed.The traditional calculation method of combining theoretical analysis with experimental formulas,and the nomograph model method by D'Appolonia for optimal determination of casting blast parameters are also introduced in detail.Blasting vibration can be considerably lowered after rationally determining the delay time between drill holes and lines.The application of extremely low density explosive or deck loading may obtain a better pre-splitting blasting result.