高程对某露天矿边坡爆破振动传播规律的影响

Influence of Elevation on the Blasting Vibration Law in the Slope of an Open-pit Mine

以马钢集团某露天铁矿为例,从爆破振动影响下边坡稳定性控制及周边建(构)筑物等的安全出发,采用爆破振动现场测试方法,开展了高程因素影响下爆破振动传播规律试验研究;采用量纲分析提出了萨道夫斯基修正公式。研究结果表明:随着高程差的增加,爆破振动速度在台阶部位岩体上存在"鞭梢效应",即表现出高程放大效应;爆破振动速度放大系数随测点至爆源水平距离的增加呈现出衰减规律,且放大系数在水平距离300 m范围内较为明显;爆破振动速度随高程差的增加以衰减为主,高程放大效应随高程差的增加而逐渐增大,且高程放大系数在高程差200 m范围内增长迅速,500 m后趋于稳定;高程差的存在增大了爆破振动危害。采用修正的萨道夫斯基公式提高了矿山边坡爆破振动速度预测的精确性,对于采场边坡及周边设施的安全控制具有指导意义。

Taking an open-pit iron mine of Magang Group as an example,the blasting vibration in-situ test method is car-ried out to study the blasting vibration propagation law by considering the elevation factor,from the aspects of slope stabilityand surrounding buildings safety under the influence of blasting vibration.The modified Sadowski formula is proposed by usingdimension analysis method.The study results show that with the increasing of elevation difference,the ＂whipping effect＂ ofblasting vibration velocity is existed on the rock mass in the bench,that is to say,the ＂ whipping effect＂ is equals to height am-plification effect;with the increasing of the horizontal distance of measurement points and explosive source,the attenuation lawof the amplification coefficient of blasting vibration is presented,and the amplification coefficient is significant in the horizontaldistance range of 300 m;with the increasing of evaluation difference,the blasting vibration is mainly attenuated,the evaluationamplification effect is increased gradually with the increasing of evaluation difference,the evaluation amplification coefficient isincreased rapidly in the evaluation difference range of 200 m,it tends to stable after 500 m;the blasting vibration hazard is in-creased by the existence of evaluation difference.The prediction accuracy of blasting vibration velocity is improved by adoptingthe modified Sadowski formula proposed in this paper,which has some guidance significance for safety controlling of stope slopeand its surrounding facilities.