Study to the Blasting-induced Vibration Monitored in High In-situ Stress Area by Wavelet Analysis
Theoretical study indicated that the Vibration Induced by blast Excavating process under high in-situ stress condition consists of Vibration Induced by Blasting load (VIB) and Vibration Induced by in-situ stress Dynamic(or transient) Unloading (VIDU). In this paper, the vibration monitored in the process of blasting excavation under both low and high geostress condition are analyzed with the help of wavelet transform. Firstly, the arriving moment of VIDU in the monitoring vibration is identified, employing the time-energy density analysis based on the wavelet transform method. Secondly, by means of the wavelet packet analysis technique, the energy distribution of the monitoring vibrations on different frequency bands is studied. The result reveals that VIDU falls behind the VIB for about 10～100ms in the monitoring vibration signals corresponding to every millisecond delay of blast, which is in accordance with theoretical analysis and the results of high-speed photography experiments. And the frequency bands of the vibration monitored in high geo-stress area and in low geo-stress area are both within 0～250 Hz, while the proportion of low frequency energy of the former is higher than that of the latter,which indicates that the VIDU contains much more low frequency energy and is much more harmful to the underground structures than VIB.
in-situ stress Blasting-induced vibration dynamic unloading wavelet transform time-energy analysis
YAN Peng LU Wenbo CHEN Ming SHU Daqiang
State Key Laboratory of Water Resources and Hydropower Engineering Science, Wuhan University, Wuhan, China
国际会议
The Second Asian-Pacific Symposium on Blasting Techniques(第二届亚太地区爆破技术研讨会)
大连
英文
520-527
2009-07-01（万方平台首次上网日期，不代表论文的发表时间）