Blasting Vibration Signature Analysis Method And Its Application Research

Blasting induced vibration analysis is the foundation and prerequisite of the hazard control technology research of blasting induced vibration. Various methods of blasting induced vibration signals analysis are introduced in details, relative merits of different methods are also discussed when they are used to analyze blasting induced vibration signals in this paper. And the characteristic of bench blasting induced vibration signals of Xin Qiao mining company are analyzed with the analysis software of blasting induced vibration which is developed under the circumstances of Matlab. The conclusions are obtained as follows.(1) EXP3850 blasting induced vibration record instrument is used to measure blasting induced vibration signals, and the measured signals are analyzed by FFT, the test signal frequency, the distribution of characteristic parameters an the main natural frequency, etc. are obtained simultaneously.(2) The same blasting induced vibration signal is decomposed and reconstructed with the four wavelets of db5, db7, sym8, coif3 respectively, and it indicates that sym8 is the most suitable for blasting induced vibration signal analysis through error analyzing.(3) Five groups of measured blasting induced vibration signals are analyzed with wavelet, and its results are compared with those resulted from the spectrum analysis. It shows that with wavelet time-frequency analysis, all the information of spectrum analysis and time-freqency distribution characteristics of blasting induced vibration signals can be both obtained. And it can better reflect the characteristic of blasting induced vibration and better meet the requirements of the burst non-stationary random vibration analysis.(4) Five groups of signals are analyzed by wavelet multi-resolution analysis and wavelet packet analysis of the energy band. Compared the multi-resolution wavelet analysis and wavelet packet energy analysis, it indicates that the energy-band wavelet packet analysis is more detail. Because the high-frequency band is decomposed more narrow, and the energy distribution is more detailed, and the energy distribution of the band after detailed breakdown can be shown more clearly. Therefore, the energy-band wavelet multi-resolution analysis is suitable for analyzing the distribution of the energy concentrated in low-frequency band signals, and wavelet packet analysis is more fit in wide ones.(5) The measured blasting vibration signals is analyzed with HHT, and it obtained that the IMF component of low-frequency components are more in the EMD, and it is favorable for analyzing the blasting vibration signal and do not need to select basis function. Through Hilbert energy spectrum, the specific distribution of energy frequency can be clearly shown with time-frequency, and the signal characteristics can be depicted accurately.(6) It can be known that the frequencies of blasting induced vibration are mainly distributed between 10 and 50Hz through analyzing the bench blasting induced vibration signals tested in Xin Qiao mining site. Combined with the blasting safe regulation, it can be determined that the maximum permission vibration velocity of houses in Xin Qiao mining site is 2.3 cm/s , and the section detonation greatest dose is enhanced 41.8% compared to originally. The practice has proved that the structures of the houses are still safe after enhanced the dose.