Experimental investigation on predicting precursory changes in entropy for dominant frequency of rockburst  

基于声发射主频熵的岩爆预警实验研究

作　　者：WANG Chun-lai CHEN Zeng LIAO Ze-feng HOU Xiao-lin LI Hai-tao WANG Ai-wen LI Chang-feng QIAN Peng-fei LI Guang-yong LU Hui 王春来;陈增;廖泽锋;侯晓琳;李海涛;王爱文;李长峰;钱鹏飞;李广永;卢辉(School of Energy and Mining Engineering,China University of Mining and Technology Beijing,Beijing 100083,China;Safety Technology Branch,CCTEG China Coal Research Institute,Beijing 100013,China;School of Mechanics and Engineering,Liaoning Technology University,Fuxin 123000,China;Center for Underground Construction and Tunnelling,Colorado School of Mines,Golden,Colorado 80401,USA)

机构地区：[1]School of Energy and Mining Engineering,China University of Mining and Technology Beijing,Beijing 100083,China [2]Safety Technology Branch,CCTEG China Coal Research Institute,Beijing 100013,China [3]School of Mechanics and Engineering,Liaoning Technology University,Fuxin 123000,China [4]Center for Underground Construction and Tunnelling,Colorado School of Mines,Golden,Colorado 80401,USA

出　　处：《Journal of Central South University》2020年第10期2834-2848,共15页中南大学学报（英文版）

基　　金：Project(2017YFC0804201)supported by the National Key Research and Development Program of China;Project(51574246)supported by the National Natural Science Foundation of China;Project(2011QZ01)supported by Fundamental Research Funds for the Central Universities,China;Project(C201911362)supported by the National Training Program of Innovation and Entrepreneurship for Undergraduates,China。

摘　　要：Rockburst is a dynamic phenomenon accompanied by acoustic emission(AE)activities.It is difficult to predict rockburst accurately.Based on the fast Fourier transform(FFT)method and the information entropy theory,the evolution model of dominant frequency entropy was established.The AE energy,frequency and stress were synthetically considered to predict rockburst.Under the triaxial and the single-face unloading tests,the relationship between AE energy and the development of internal cracks was analyzed.Using the FFT method,the distribution characteristics of AE dominant frequency values were obtained.Based on the information entropy theory,the dominant frequencies evolved patterns were ascertained.It was observed that the evolution models of the dominant frequency entropy were nearly the same and shared a characteristic“undulation-decrease-rise-sharp decrease”pattern.Results show that AE energy will be released suddenly before rockburst.The density of intermediate frequency increased prior to rockburst.The dominant frequency entropy reached a relative maximum value before rockburst,and then decreased sharply.These features could be used as a precursory information for predicting rockburst.The proposed relative maximum value could be as a key point to predict rockburst.This is a meaningful attempt on predicting rockburst.岩爆是一种伴随着声发射(AE)活动的动态现象,难以准确预测。本文基于快速傅立叶变换(FFT)方法和信息熵理论,建立了主频熵的演化模型。综合考虑应力,AE能量和频率来进行岩爆预警。在三轴卸荷的试验条件下,分析了声发射参数与裂纹发育的关系,使用FFT方法获得了AE主频分布的特征。基于信息熵理论确立了主频熵的演化模型。可以观察到,实验中的主频熵演化模型几乎都呈现出“震荡—下降—小幅上升—急剧下降”的特征。结果表明,岩爆前,AE能量会突然释放,声发射的中频密度会增加。主频熵值在岩爆前达到相对最大值,然后急剧下降。这些特征可以作为岩爆预警的前兆信息,主频熵相对最大值点可以作为预测岩爆的关键点。这对于岩爆预警是一次有意义的尝试。

关 键 词：ROCKBURST precursory information acoustic emission information entropy dominant frequency evolution model 

分 类 号：TD315[矿业工程—矿井建设]