Citation

Zhao A, Ma Y, Liu J, Chen D, Yuan H, Fu M. China Saf. Sci. J. 2020; 30(3): 115-121.

Copyright

(Copyright © 2020, China Occupational Safety and Health Association, Publisher Gai Xue bao)

DOI

10.16265/j.cnki.issn1003-3033.2020.03.018

PMID

unavailable

Abstract

In order to analyze gas's influence on AE band energy during coal rupture under loading, with structural coal as research object, uni-axial compression test was carried out by using self-developed gas-containing coal test device. Then, signal processing method of fast Fourier transform (FFT) and wavelet packet analysis was used to obtain characteristics of AE band energy during coal rupture under different gas pressure. The results show that the greater gas pressure is, the larger main frequency of AE signal is, the narrower frequency band is, and spectrum transforms gradually from a complex multi-peak form to a single peak form. When three is gas, with the increase of loading stress, frequency band enriches and spectrum shifts to left gradually. As gas pressure changes, energy of 2. 92-4. 38 kHz, 4. 38-5. 84 and 7. 3-8. 76 kHz changes significantly while that in 2.92-4.38 kHz is basically same as the sum of 4.38-5.84 and 7.3-8.76 kHz, showing an opposite trend. When stress of structural coal increases, 4.38-5.84 and 7.3-8.76 kHz indicate the largest increase and decrease of energy respectively. 2.92-4. 38 kHz and 4.38-5.84 kHz can be used as characteristic frequency bands to study damage of structural coal under loading in mines with gas. © 2020 China Safety Science Journal. All rights reserved.

Language: zh