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 ev...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.展开更多
基金Project(2017YFC0804201)supported by the National Key Research and Development Program of ChinaProject(51574246)supported by the National Natural Science Foundation of China+1 种基金Project(2011QZ01)supported by Fundamental Research Funds for the Central Universities,ChinaProject(C201911362)supported by the National Training Program of Innovation and Entrepreneurship for Undergraduates,China。
文摘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.
