邻近矿柱浅孔落矿不耦合装药爆破损伤控制的数值模拟研究

采用ANSYS/LS-DYNA三维非线性动力有限元软件对浅孔落矿邻近矿柱炮孔不耦合装药结构进行了数值模拟, 引入岩体爆破损伤的质点峰值震动速度安全判据及爆破损伤范围计算式, 分析了矿房和矿柱的爆破损伤范围, 采用爆破荷载下岩石Von Mises屈服准则分析了矿柱与其邻近炮孔的安全距离。结果表明: 随着炮孔不耦合系数增加, 爆破对矿柱损伤范围逐渐减小, 不耦合系数为1.38(炮孔直径为44 mm)时, 爆破对矿柱的损伤范围约为0.15 m, 相对于其他孔径的炮孔对矿柱的爆破损伤范围较小。邻近矿柱炮孔合理的装药结构能有效控制爆破损伤范围, 不同耦合条件下炸药爆炸矿柱稳定性与炮孔的距离有关。该研究为优化类似矿山的安全开采爆破参数具有一定参考依据。

Study on Blasting Damage Control with Decoupled Charges for Adjacent Pillars in Short Hole Mining by Numerical Simulation

A numerical simulation was performed using ANSYS/LS-DYNA 3D nonlinear dynamic finite element software, for short hole mining using decoupled charges of adjacent pillars. Safety criterion in terms of peak particle velocity for determining the orebody blasting damage and equation for calculating blasting damage were introduced to analyze the extent of damage of room and pillars caused by blasting. Von Mises yield criterion for rock masses under the action of blasting load was used to analyze the safe distance between pillars and blastholes. It is found that with the increase of the decoupling coefficient of blastholes, the extent of damage to the pillars caused by blasting is diminishing. When the decoupling coefficient is 1.38 (the blasthole with diameter of 44 mm), the damage to pillars by blasting is controlled within the range of 0.15 m, lesser damage compared to that with blastholes in other diameters. It is concluded that a proper arrangement of charges for  adjacent pillars can effectively reduce the scope of damage. The stability of pillars caused by blasting with different coupling conditions is dependent on the distance between blastholes. This study may be of reference for optimizing blasting parameters of safe mining in other similar mine.