深孔台阶爆破近远区振动特征的试验研究

Experimental study on vibration characteristics of deep hole bench blasting in both near and far field

为了探索深孔台阶爆破在近区和远区的振动特征,以现场试验为基础,利用回归分析、随机分析及小波包分解技术,从爆破振动信号的衰减规律、三分量特征、随机特征及能量分布等方面对二者进行了对比研究,结果显示:振速三分量在近区的K、α值均大于远区,远区各分量的α值更为接近。振速三分量在远区的相关系数大于近区,且更接近1,三分量中垂向分量的相关系数最大。近区当比例距离小于5时,径向振速最大,比例距离大于等于5时,垂向振速最大。远区的垂向振速最大。无论在近区还是远区,切向振速一般最小。振速三分量在近区的变异系数大于远区,径向振速的变异系数在近区和远区较为接近。最大段药量或爆心距增加时,近区及远区的能量均向低频带流动,近区的移动速度更快,同时近区及远区能量分布的频带宽度也将趋于集中,近区的频带宽度更宽。

In order to explore the vibration characteristics of deep hole blasting in near and far field, based on field test, this paper used the regression analysis, random analysis and wavelet packet decomposition to carry on a comparative study from the attenuation, three-component characteristic, random characteristic and energy distribution of blasting vibration signals. The results show that the values of K and α of the three-component of vibration velocity in the near field are both greater than those in the far field. The value of α of each component in the far field is closer to each other. The correlation coefficient of the three-component vibration velocity in the far field is greater than that in the near field, and closer to 1. The vertical component in the three components is the largest. In the near field, when the scaled distance is less than 5, the radial velocity is the largest, otherwise, the vertical velocity is the largest. In the far field, the vertical velocity is always the largest. Both in the near and far field, the tangential velocity is generally minimal. The coefficient of variation of the three components of vibration velocity in the near field is larger than that in the far field, and the coefficient of variation of the radial velocity are close in the near and far field. When the maximum charge weight per delayed interval or distance is increased, energy in the near and far field gradually move toward the low frequency band, in which it moved faster in near field. At the same time, the frequency band width of energy distribution in the near and far field also tend to focus, and the frequency band width in near field is larger. © 2017, Editorial Office of Journal of Vibration and Shock. All right reserved.