Energy characteristics of AE signal frequency band during coal rupture in mines with gas

doi:10.16265/j.cnki.issn1003-3033.2020.03.018

Abstract

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.

Key words: gas pressure, coal, acoustic emission (AE), uni-axial compression, frequency band energy

CLC Number:

X936

ZHAO Aohan, MA Yankun, LIU Jian, CHEN Dezhong, YUAN Hongyong, FU Ming. Energy characteristics of AE signal frequency band during coal rupture in mines with gas[J]. China Safety Science Journal, 2020, 30(3): 115-121.

References

[1] WANG Chaojie, YANG Shengqiang, YANG Dingding, et al. Experimental analysis of the intensity and evolution of coal and gas outbursts[J]. Fuel,2018,226: 252-262.
[2] 王雨虹,刘璐璐,付华,等.基于声发射多参数时间序列的瓦斯突出预测[J].中国安全科学学报,2018,28(5): 129-134.
WANG Yuhong, LIU Lulu, FU Hua, et al. Research on acoustic emission multi-parameter time series based prediction of gas outburst [J]. China Safety Science Journal, 2018,28 (5): 129-134.
[3] LEI Xinglin, TAKAHIRO F, MA Shengli,et al. A laboratory acoustic emission experiment and numerical simulation of rock fracture driven by a high-pressure fluid source[J]. Journal of Rock Mechanics and Geotechnical Engineering, 2016,8 (1): 27-34.
[4] 赖于树,熊燕,程龙飞.受载混凝土破坏全过程声发射信号频带能量特征[J].振动与冲击,2014,33(10): 177-182.
LAI Yushu, XIONG Yan, CHENG Longfei. Frequency band energy characteristics of acoustic emission signals In damage process of concrete under uniaxial compression [J]. Journal of Vibration and Shock, 2014, 33(10): 177-182.
[5] CAI M, KAISER P K, MORIOKA H, et al. FLAC/PFC coupled numerical simulation of AE in large-scale underground excavations[J].International Journal of Rock Mechanics & Mining Sciences, 2006, 44(4): 550-564.
[6] 何满潮,赵菲,张昱,等.瞬时应变型岩爆模拟试验中花岗岩主频特征演化规律分析[J].岩土力学,2015,36(1):1-8,33.
HE Manchao, ZHAO Fei, ZHANG Yu,et al. Feature evolution of dominant frequency components in acoustic emissions ofinstantaneous strain-type granitic rockburst simulation tests [J]. Rock and Soil Mechanics, 2015,36 (1): 1-8,33.
[7] 刘祥鑫,张艳博,梁正召,等.岩石破裂失稳声发射监测频段信息识别研究[J].岩土工程学报,2017,39(6): 1 096-1 105.
LIU Xiangxin, ZHANG Yanbo, LIANG Zhengzhao, et al. Recognition of frequency information in acoustic emission monitoring of rock fracture [J]. Chinese Journal of Geotechnical Engineering, 2017,39 (6): 1 096-1 105.
[8] 曾鹏,刘阳军,纪洪广,等.单轴压缩下粗砂岩临界破坏的多频段声发射耦合判据和前兆识别特征[J]. 岩土工程学报, 2016, 39(3): 509-517.
ZENG Peng, LIU Yangjun, JI Hongguang, et al. Coupling criteria and precursor identification characteristics of multi-band acoustic emission of gritstone fracture under uniaxial compression [J]. Chinese Journal of Geotechnical Engineering, 2016, 39 (3): 509-517.
[9] 王恩元,何学秋,刘贞堂,等.煤体破裂声发射的频谱特征研究[J].煤炭学报,2004,29(3): 289-292.
WANG Enyuan, HE Xueqiu, LIU Zhentang, et al. Study on frequency spectrum characteristics of acoustic emission in coal or rock deformation and fracture [J]. Journal of China Coal Society, 2004,29 (3): 289-292.
[10] LOU Quan, SONG Dazhao, HE Xueqiu, et al. Correlations between acoustic and electromagnetic emissions and stress drop induced by burst-prone coal and rock fracture[J]. Safety Science, 2019, 115: 310-319.
[11] LIU Shumin, LI Xuelong, LI Zhonghui,et al. Energy distribution and fractal characterization of acoustic emission (AE) during coal deformation and fracturing[J]. Measurement, 2019,136: 122-131.
[12] 李宏艳,康立军,徐子杰,等.不同冲击倾向煤体失稳破坏声发射先兆信息分析[J]. 煤炭学报, 2014, 39(2): 384-388.
LI Hongyan, KANG Lijun, XU Zijie, et al. Precursor information analysis on acoustic emission of coal with different outburst proneness [J]. Journal of China Coal Society, 2014, 39 (2): 384-388.
[13] 王汉鹏,张庆贺,袁亮,等.含瓦斯煤相似材料研制及其突出试验应用[J].岩土力学,2015,36(6): 1 676-1 682.
WANG Hanpeng, ZHANG Qinghe, YUAN Liang. et al. Development of a similar material for methane-bearing coal an its application to outburst experiment [J]. Rock and Soil Mechanics, 2015, 36 (6): 1 676-1 682.
[14] DAVIDE B, ERWIN M, MARTIN G, et al. Wavelet packet transform for detection of single events in acoustic emission signals[J]. Mechanical Systems and Signal Processing, 2015, 64/65: 441-451.
[15] HUO Haiye, SUN Wenchang. Sampling theorems and error estimates for random signals in the linear canonical transform domain[J]. Signal Processing, 2015,111: 31-38.
[16] 秦虎,黄滚,蒋长宝,等.不同瓦斯压力下煤岩声发射特征试验研究[J].岩石力学与工程学报, 2013,32(增2): 3 719-3 725.
QIN Hu, HUANG Gun, JIANG Changbao, et al. Experimental research on acoustic emission characteristics of coal and rock under different gas pressures [J]. Chinese Journal of Rock Mechanics and Engineering, 2013,32 (S2): 3 719-3 725.