隧道衬砌混凝土爆破振动能量传播规律试验

Experimental Study on Energy Propagation Law of Blasting Vibration Signals for Tunnel Lining Concrete

针对隧道衬砌混凝土频繁爆破振动危害累积效应,设计混凝土频繁爆破振动试验,对测得的爆破振动信号进行总能量和频带能量计算与分析。试验结果表明:①爆破振动信号能量分布范围较广;但绝大部分能量集中在 0 ~ 205. 08 Hz;且多以9. 77 ~58. 59 Hz 频带能量较大;②总能量随距离的增大而减小,在近区衰减迅速,中远区较近区衰减缓慢;而能量随着距离的增大向低频带集中,且距离越大越明显;③总能量随爆破次数增加呈降低趋势,其中近区测点的总能量在大值范围内下降;而中远区衰减较为平缓。能量集中频带随爆破次数增加总体向中低频段发展;且近区测点在低频段能量所占比例有所增加。

Under frequent blasting,there is the cumulative effect of vibration hazard for the tunnel lining concrete. Therefore,frequent blasting vibration test was designed for the lining concrete in laboratory. The total energy and frequency band energy of the blasting vibration signals were caculated and analyzed. The results showed that: blasting vibration signals had a wide range of energy distribution,but most of the energy was concentrated in 0 ~ 205. 08 Hz,and the maximum energy was in 9. 77 ~58. 59 Hz. The total energy decreased with the increase of distance,rapidly in the near region and slowly in the middle and far region. The energy concentrated in the low fre- quency band,and the greater the distance was,the more obvious. The total energy decreased with the increase of blasting times,and the total energy of near-field points decreased in a large range,the attenuation of far-field points was more gentle. With the increase of blasting times,the energy concentrated frequency band was generally in the middle and low frequency bands,and the proportion of the low frequency band in the near-field points had increased to a certain extent.