文献类型：期刊文献

英文题名：Identification of crack development in granite under triaxial compression based on the acoustic emission signal

作者：Wang, Tianzuo[1,2];Wang, Linxiang[1];Xue, Fei[1,2];Xue, Mengya[1]

机构：[1]Shaoxing Univ, Coll Civil Engn, Key Lab Rock Mech & Geohazards Zhejiang Prov, Shaoxing 312000, Zhejiang, Peoples R China;[2]Zhejiang Collaborat Innovat Ctr Prevent & Control, Shaoxing, Peoples R China

年份：2021

卷号：17

期号：1

外文期刊名：INTERNATIONAL JOURNAL OF DISTRIBUTED SENSOR NETWORKS

收录：SCI-EXPANDED(收录号：WOS:000610418900001)、、EI(收录号：20210309768922)、Scopus(收录号：2-s2.0-85099222599)、WOS

基金：The author(s) disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: This study was financially supported by the Second Tibetan Plateau Scientific Expedition and Research Program (Grant No. 2019QZKK0904), the National Natural Science Foundation of China (Grant No. 41831290), and the Natural Science Foundation of Zhejiang Province (Grant No. LQ20E080006).

语种：英文

外文关键词：Dominant frequency; granite; triaxial compression; Fourier transform; crack identification

外文摘要：To explore the development mechanism of cracks in the process of rock failure, triaxial compression tests with simultaneous acoustic emission monitoring were performed on granite specimens using the MTS rock mechanics test system. The frequency-domain information of the acoustic emission signal was obtained by the fast Fourier transform. The Gutenberg-Richter law was used to calculate the acoustic emission signals and obtain the b-value dynamic curve in the loading process. Combined with the stiffness curve of granite specimens and acoustic emission signal in the time domain and frequency domain, the crack development characteristics in different stages were analyzed. The results showed that the acoustic emission signals of granite samples under triaxial compression can be divided into four stages: quiet period 1, active stage 1, quiet period 2, and active stage 2. b-value attained its maximum value in the active phase 2 when it is close to the sample loss, and then drops rapidly, which means the propagation of cracks and the formation of large cracks. The acoustic emission signal's dominant frequency was not more than 500 kHz, mostly concentrated in the medium-frequency band (100-200 kHz), which accounted for more than 80%. The proportion of signals in each frequency band can reflect the distribution of the three kinds of cracks, while the change in low-frequency signals can reflect the breakthrough of microcracks and the formation time of macrocracks in granite samples. By fully analyzing the characteristics of acoustic emission signals in the time domain and frequency domain, the time and conditions of producing large cracks can be determined accurately and efficiently.