Blasting blind shot detection method

Abstract

The invention discloses a blind shot phenomenon occurring in a blast working process, provides an improved algorithm based on EMD and a cross-correlation function, is named as CEMD, and can realize accurate detection of blasting blind shots. The specific method comprises the following steps of firstly, conducting adaptive decomposition on a blasting vibration signal by using EMD to obtain a series of IMF components, constructing a principal component screening model by using a cross-correlation function, then extracting a principal component envelope line by Hilbert transform, calculating the delay of an envelope line peak point, and comparing the delay with the actual delay of blast hole blasting to realize blind shot detection. In order to check the effectiveness of the method, the method is applied to tunnel blasting blind shot detection. Results show that the blind shot detection accuracy of a vibration waveform method, a wavelet time-energy density method and a CEMD method is 11%, 62% and 100% respectively, and the CEMD blind shot detection method is superior to a high-precision magnetic method, a transient electromagnetic method and a frequency division multiple access method in terms of five indexes including blast hole size, detection distance, detection precision, geological conditions and use cost.

Description

technical field [0001] The invention relates to the field of blasting, in particular to a method for blind shot detection of blasting. Background technique [0002] During the blasting construction process, due to the influence of blasting equipment quality, blasting design and construction, and other factors, blind blasting incidents are prone to occur. Blind shots not only seriously affect the blasting effect, but also bring huge safety hazards. However, blind shots cannot be completely avoided in blasting engineering. How to quickly and efficiently detect blind shots has become a research hotspot and difficulty in the field of engineering blasting. At present, blind shot detection methods can be generally classified into two categories: one is geophysical detection method, including high-precision magnetic method, transient electromagnetic method and frequency division multiple access method. Among them, the principle of high-precision magnetic method is to use the prefa...

AI Technical Summary

Problems solved by technology

Zhang Yiping used the empirical mode decomposition to extract the peak point of the blasting seismic wave principal component envelope to detect the blasting delay time. Compared with the wavelet method, it does not need to choose the wavelet function, and it is self-adaptive, and the detection accuracy is greatly improved. However, EMD ( The Empirical Mode Decomposition) detection method usually selects the principal component according to the amplitude of the decomposed IMF (Intrinsic Mode Function) component and the attenuation characteristics of the waveform, which will lose the original information of the blasting seismic wave

Images