基于ALE算法的单孔台阶爆破数值模拟研究

岩石在炸药爆炸荷载作用下,其瞬态破坏过程难以用现有的技术进行有效的监测。为研究在台阶爆破中岩石的破碎及抛掷过程,采用LS-DYNA建立单孔台阶爆破三维数值计算模型,通过ALE算法并结合流固耦合定义岩石和炸药的接触,模拟炸药在炮孔内爆炸的全过程。分析了炮孔内炸药的爆轰过程及其压力极值分布、岩石裂纹的形成和拓展的宏观现象、岩石的块度分布及其抛掷过程。模拟计算结果显示,炮孔粉碎区半径为装药半径的3.9倍,坡面破碎岩石的最大抛掷速度为73.8m/s。采用ALE法模拟单孔台阶爆破,其爆破效果与现有工程实际相吻合,可以为工程爆破参数的设计和优化提供参考。

Numerical simulation of single hole bench blasting based on ALE method

The process of transient damage on the rocks, which is exposed to the loading of blasting, is pretty hard to monitor by current technology. In order to study the crush and throwing process of rocks in bench blasting, the whole process of blasting is simulated. More specifically, a 3D numerical model of single hole bench blasting is established by LS-DYNA through the ALE algorithm, which is accompanied by fluid-solid interaction method to define the contact of rocks and explosives. Then, the whole blasting process have been systematically analyzed, such as detonation and its extreme value of explosives in blasthole, formation and extension of rock cracks, distribution and throwing process of rocks. The results reveal that radius of crushing zone is 3.9 times than the radius of charging, and the throwing velocity of fragmented rock on slope is maximum at 73.8 m/s. Overall, the simulated blasting effect is coincide with realistic situations.