为减少岩石大块率和粉碎率,增强爆破效果,采用LS-DYNA数值模拟的方法对连云港核电扩建山体爆破工程爆破碎石的力学过程和能量利用率进行了理论分析,并通过对各模型进入岩石总能量峰值的对比,分析了孔底惰性介质间隔装药对能量利用率的影响趋势,然后依托工程开展全尺寸实验。实验结果表明:孔底适量惰性介质间隔装药可以改善应力波的传播条件,使爆炸能量更均匀、充分地传入岩石中,使岩块的破碎效果得到有效改善;实验工况下,孔底间隔80、100cm空气柱,炸药单耗分别下降11.5%、13.5%;孔底间隔80、100cm水柱,炸药单耗分别下降17.3%、19.2%。
In order to reduce the rock bulk rate and crushing rate and enhance the blasting effect, the mechanical process and energy utilization rate of blasting crushing were analyzed by LS-DYNA numerical simulation method based on Lianyungang nuclear power mountain expansion blasting project.The total energy peaks of each model were compared and the influence of the bottom inert medium in deck charging on the energy utilization rate was analyzed.The full-scale experiment relying on the engineering showed that, moderate amount of inert medium interval charge could improve the propagation of stress wave conditions, which made the explosive energy more uniform and fully into the rock, that the effect of rock fragments of the rock mass was improved effectively.In the conditions like the engineering, the explosive unit consumption decreased by 11.5% and 13.5% respectively for 80 cm and 100 cm deck air column in bottom of the blasthole, and the explosive unit consumption decreased by 17.3% and 19.2% respectively for 80 cm and 100 cm deck water column in bottom.