基于EEMD-HHT法的露天矿山深孔爆破振动效应研究

Study on Vibration Effect of Deep Hole Blasting in Open-pit Mine Based on EEMD-HHT

工程爆破在我国国民经济建设过程中发挥着重要的作用,但作为爆破有害效应之首的爆破振动是一个不可忽视的问题。为研究露天矿山深孔控制爆破“高程效应”“鞭梢效应”以及爆破振动波能量分布特征,依托星光露天矿山深孔控制爆破工程,通过现场爆破试验研究,提出了一种基于电子雷管精确延时与EEMD-HHT信号分析技术的爆破振动效应分析方法。研究表明:爆破振动速度总体呈现衰减趋势,存在高程放大效应,且具有明显的方向性,放大系数表现为垂向(Z方向)>径向(X方向)>切向(Y方向);同一高程,“鞭梢效应”现象明显,表现为台阶外缘附近岩体质点峰值振动速度大于内缘边坡坡脚处;爆破振动信号能量优势频段分布于10~50 Hz,并且以低频段为主,爆破振动波能量垂向(Z方向)>切向(Y方向)>径向(X方向)。通过对露天矿山深孔控制爆破振动效应的研究,降低了爆破振动对岩体扰动的影响,爆后边坡岩体稳定,轮廓清晰,破岩块度均匀,为类似工程提供了参考依据。

Engineering blasting plays an important role in the process of national economic construction in China,but blasting vibration,as the first harmful effect of blasting,is a problem that can not be ignored.In order to study the"elevation effect","whiplash effect"and the energy distribution characteristics of blasting vibration wave in deep-hole controlled blasting in open-pit mine,a method for analyzing blasting vibration effect based on the precise delay of electronic detonator and EEMDHHT signal analysis technology is proposed in this paper,relying on the deep-hole controlled blasting project in Xingguang Open-pit Mine and through field blasting test.The test and analysis results show that the blasting vibration velocity shows attenuation trend,and there is elevation amplification effect with obvious directivity.The amplification coefficient is vertical(Z direction)>radial(X direction)>tangential(Y direction).At the same elevation,the phenomenon of"whiplash effect"is obvious,which shows that the peak vibration velocity of rock mass near the outer edge of the step is greater than that at the foot of the inner edge slope.The dominant frequency band of blasting vibration signal energy is distributed in 10~50 Hz,and mainly in low frequency band.The energy of blasting vibration wave is vertical(Z direction)>tangential(Y direction)>radial(X direction).Through the study on the vibration effect of deep-hole controlled blasting in open-pit mine,the influence of blasting vibration on rock mass disturbance is reduced,and the slope rock mass is stable,the outline is clear and the broken rock mass is uniform after blasting,which provides reference for similar engineering.