作者：王云刚；王庆军；魏建平；雷东记

第一作者单位：河南省瓦斯地质与瓦斯治理重点实验室-省部共建国家重点实验室培育基地；河南理工大学安全科学与工程学院；煤炭安全生产河南省协同创新中心

摘要：次声波技术有望成为监测、预警矿井煤岩动力灾害的新技术,其中,次声信号的频率特征是应用研究的关键参数。对煤样进行单轴压缩试验,采用次声信号监测系统对煤样在变形破裂过程中产生的信号实时采集,借助小波包变换信号分析方法分析信号的能量分布特征。结果表明:(1)小波包变换可将信号精细分割成各个频带,不但可以起到滤波的作用,而且可对所研究的频率范围进行分析。(2)煤样破裂次声信号与应力在时间上有很好的对应关系,特别是次声信号对应力降表现为明显的突变。应力降在一定程度上反映宏观裂纹的出现,说明次声信号对宏观裂纹有很好的敏感性。(3)煤样破裂次声信号的频率在0~20 Hz间均有分布,但主要集中在3.125~12.5 Hz与18.75~21.875 Hz间。小波包变换信号分析方法及煤样破裂次声信号频率特征可为进一步研究提供方法和参考。

Abstract：Infrasonic wave technology is expected to become a new method to monitor and warn the dynamic disasters of coal and rock in coal mine, and the frequency characteristics of infrasonic signal are the key parameters of application research. Through the uniaxial compression test of coal specimens, the infrasonic signal monitoring system is used to collect the signals produced by the coal specimen in the process of deformation and fracture. The energy distribution characteristics of the signal were analyzed by means of wavelet packet transform. The experiment results show: (1) Wavelet packet transform can fine signal segmentation into each frequency band, and can play an role in filtering, the frequency range of the analysis. (2) There is a good correspondence between the infrasonic signals of coal specimen burst and the stress in the time, especially the infrasonic signal shows a significant mutation during stress drop. The stress drop reflects the emergence of macroscopic cracks to some extent, indicating that infrasonic signal has a good sensitivity to macroscopic cracks. (3) The frequency of the infrasonic signals of coal specimen burst are all distributed in 0 ~ 20 Hz, but mainly in3. 125 ~ 12. 5 Hz and 18. 75 ~ 21. 875 Hz. The signal analysis method with wavelet packet transform and the frequency characteristics of the infrasonic signals of coal specimen burst can provide the study basis and reference for further research.

关键词：次声波;小波包变换;单轴压缩;煤岩动力灾害;

DOI：10.16186/j.cnki.1673-9787.2018.02.001

分类号：TD315