Analysis on the Possibility of Eliminating Interference from Paraseismic Vibration Signals Induced by the Detonation of Explosive Materials

Abstract

This article presents the results of studies on the impact of acoustic waves on geophones and microphones used to measure airblasts carried out in a reverberation chamber. During the tests, a number of test signals were generated, of which two are presented in this article: frequency-modulated sine (sine sweep) waves in the 30–300 Hz range, and the result of detonating 3 g of pyrotechnic material inside the chamber. Then, based on the short-time Fourier transform, the spectral subtraction method was used to remove unwanted disruption interfering with the recorded signal. Using MATLAB software, a program was written that was calibrated and adapted to the specifics of the measuring equipment based on the collected test results. As a result, it was possible to clean the signals of interference and obtain a vibration signal propagated by the substrate. The results are based on signals registered in the laboratory and made in field conditions during the detonation of explosive materials.

Issues of Data Acquisition and Interpretation of Paraseismic Measuring Signals Triggered by the Detonation of Explosive Charges

“…This paper constitutes the first part of the results of the study aimed to show how difficult it is to acquire and interpret measurement data recorded during the detonation of explosive materials. The results of the tests carried out in a reverberation chamber as well as the results of filtering analysis that eliminates air-propagated interference will be presented in the next paper [ 35 ], so it is possible to install the sensor without a shield, but it requires simultaneous measurement of vibration and pressure of the air shock wave.…”

“…Based on the conducted research and preliminary analysis, it can be concluded that the problem of measuring the impact of vibrations and air shock waves resulting from the detonation of explosive charges is a difficult issue and requires extensive experience, both when performing tests and analysing their results. Due to the more and more frequent execution of blasting works in the vicinity of buildings, it is necessary to apply new methods of vibration forecasting [ 36 ] or their analysis [ 12 , 35 , 37 ]. Thanks to this, it is possible to increase the credibility of the forecast and at the same time to a greater degree control the negative impact to environment of the blasting works performed.…”

Measurement method for electromagnetic radiation generated during a high-capacity warhead explosion

“…The variation in the vibration amplitude of seismic waves in an explosive field is related to factors such as the distance, charge amount, and geological conditions. Taking the explosive or warhead equivalent Q, charge density ρ e , and chemical energy released by the unit mass explosive E e as basic quantities, the dimensionless relationship shown in equation ( 1) can be obtained [25]. In equation (1), γ e is the expansion index of the explosive product, p a is the initial pressure of air, ρ a is the initial density of air, γ a is the adiabatic index, d is the explosion center distance, ρ g is the density of the seismic wave propagation medium is ρ g , E g is the elastic modulus of the medium is E g , and…”