爆炸荷载下露天矿高陡边坡动力响应分析

为研究矿山高陡边坡在爆炸荷载作用下的动力响应规律,采用LS-DYNA软件,对威斯特铜矿的采场边坡进行完全动力有限元计算。对比分析了数值模拟和现场实测环境下爆炸应力波的传播规律,两者结果相接近。同时,通过对各台阶爆破振动速度的统计分析可知,随着台阶高程的增加,在台阶坡顶、台阶边缘至台阶内侧坡脚的1/3至1/2距离处容易产生高程放大效应。另外,利用极限平衡法原理,结合数值模拟计算结果,计算了在炸药起爆后400ms内边坡的时程安全系数,直观描述了爆破动力荷载对边坡稳定性的影响。

Dynamic response analysis of high and steep slope in open pit mine under blast loading

In order to study the dynamic response of a high and steep slope under blast loading, the 3D model of West Copper Mine has been completely dynamic simulated by LS-DYNA program. Then, compared with the numerical simulation and field test results of blasting stress wave propagation rules, both results are close to each other. Meanwhile, with the increasing of elevation, the vibration speed amplification effect is produced on top of the step or 1/3 to 1/2 times distance from the edge to the toe. Besides, the time-history safety factors have been calculated in 400 ms after the explosive detonation based on the principle of the limit equilibrium method and the results of dynamic simulation. The time-history safety factors intuitively describe the effects of slope stability under blast loading.