微差时间及柱状装药特征对爆破振动效应影响研究

Study on the blasting vibration effect influenced by millisecond time and cylindrical charging characteristics

为了研究炮孔装药特征及微差时间对爆破振动效应影响,根据短柱装药爆破产生振动波的特点,研究双孔微差爆破振速的局部放大效应,同时在短柱装药爆破的基础上,研究长柱装药特征及起爆方式对炸药爆破振动效应的影响,得到长柱装药爆破下,药包长度、爆轰速度、埋置深度、起爆方式及围岩介质变化等对质点振速的影响,并利用萨氏公式拟合了柱状装药爆破下质点峰值速度。分析表明:局部放大效应的幅值及范围与微差时间和爆破荷载衰减系数密切相关。对于药包顶端以下点,当装药长度增加到一定程度时,质点振速不再随之增加,同时爆轰速度对爆破振动效应的影响也只限制在一定速度范围内。对于药包顶端以上点,柱状装药埋置长度越长,地表振速越大。不同的起爆方式下,底部起爆振速最大,其次是两端起爆,最小的是顶端起爆。距离爆源越近处的质点的振动效应受围岩介质变化影响越明显。柱状装药拟合得到的萨氏公式能较好地表征出长柱装药爆破振动峰值速度特点,球状装药拟合得到的萨氏公式不能表示长柱装药爆破振动特征。

In order to study the blasting vibration effect influenced by charging characteristics and millisecond time,the local amplification effect of blasting vibration velocity in double-hole blasting is discussed by analyzing the characteristics of vibration wave generated by finite length cylindrical charge.Meanwhile,the particle vibration effects of rock induced by long cylindrical charging characteristics and different initiation modes are analyzed.The effects of charge length,explosive detonation velocity,charge depth,initiation mode and rock characteristics on the blasting vibration are obtained.Besides,the peak particle velocity of long cylindrical charge is fitted with the Sadov？s formula.The results show that the magnitude and scope of the local enlargement are closely related to the millisecond time and blasting attenuation coefficient.The blasting vibration velocity would no longer increase when the charge length increases to a certain extent for the measuring point below the top of the charge.Besides,the effect of detonation velocity on blasting vibration is only limited in a certain velocity range.For the measuring point above the top of the charge,the particle velocity on the surface grows bigger with the increasing of charging buried depth.For different initiation modes,the peak particle velocity is the maximum at bottom initiation,the second is both ends initiation,and the peak particle velocity is the minimum at top initiation.When the measuring point is closer to the source,the more obvious vibration affected by the rock characteristics change.The fitted Sadov？s formula of cylindrical charge can well indicate the peak velocity characteristic of the blasting vibration of cylindrical charge.The fitted Sadov＇s formula of spherical charge cannot denote the vibration characteristic of cylindrical charge.