缓冲孔对爆破振动信号幅频特性影响研究

为探索缓冲孔对爆破振动信号的峰值质点振动速度、主振频率和各频带能量分布等的影响,依托贵州某露天矿临近边坡爆破振动试验,获得了现场主爆破和缓冲爆破的振动信号。分别采用小波包分析和数值模拟方法对采用主爆破和缓冲爆破的振动信号进行分析。结果表明,临近边坡缓冲爆破具有明显的减震效应。相同测点条件下,水平切向振动信号的减振率最大,减振效果最好。且随着测点距爆源的距离越近,其减振效果越好。爆破振动信号的能量主要集中于60 Hz以内且分布极不均匀,存在多个主振频带。设置缓冲孔进行临近边坡爆破时,其振动信号的能量更向高频的主振频带集中,有利于避开边坡的自振频率。

Effects of buffer hole on amplitude-frequency features of blast vibration signals

In order to investigate effects of buffer hole on blast vibration signals’ peak vibration velocity, main vibration frequencies and frequency band energy distribution, blast vibration tests of adjacent slope in a certain open-pit mine of Guizhou province were conducted to get blast vibration signals without and with buffer holes onsite. The wavelet packet analysis method and the numerical simulation one were used to analyze these vibration signals, respectively. The results showed that adjacent slope buffer blast has obvious vibration reduction effect; under the same measurement conditions, horizontal tangential vibration signals have the maximum vibration reduction rate and the best vibration reduction effect; the more close to explosion source, the better vibration reduction effect; blast vibration energy signals’ energy is concentrated in the range of 0-60 Hz and energy distribution is extremely uneven with several main vibration frequency bands; when performing adjacent slope blast with buffer holes, blast vibration signals’ energy is more focused on main vibration frequency bands of high frequency, and avoids natural vibration frequencies of slope. 