Experimental study on incubation and acoustic emission characteristics of rock fracture process zones

被引：0

作者：

An D. ^{[1
]}

Zhang S. ^{[1
,2
]}

Zhang X. ^{[1
]}

Yu B. ^{[1
]}

Wang H. ^{[1
]}

机构：

[1] College of Energy Science and Engineering, Henan Polytechnic University, Jiaozuo

[2] The Collaborative Innovation Center of Coal Safety Production of Henan Province, Jiaozuo

来源：

Yanshilixue Yu Gongcheng Xuebao/Chinese Journal of Rock Mechanics and Engineering | 2021年 / 40卷 / 02期

基金：

中国国家自然科学基金;

关键词：

Acoustic emission; Digital image correlation method; Failure mode; Inoculation; Length of fracture process zone; Rock mechanics;

D O I：

10.13722/j.cnki.jrme.2020.0752

中图分类号：

学科分类号：

摘要：

In order to study the inoculation law and acoustic emission characteristics of rock fracture process zones, straight-crack disc sandstone samples were used for the split loading test on the GCTS rock test system, the real-time monitoring was performed with the help of digital image correlation method(DICM) and acoustic emission(AE) instrument, and the lengths of sample fracture process zones were obtained according to the change of the horizontal displacement of measuring lines near crack tips and the AE event locations. The theoretical value of the fracture process zone length was determined based on the high-order term of Williams series expansion as well as the revised maximum tangential stress criterion, and the failure morphology of the specimens was discussed. The results show that the average values of the fracture process zone length determined by DICM and theoretical calculation are respectively 9.07 mm and 5.19 mm, and the difference between them is due to that the theory method fails to consider the influence of the microscopic characteristics of the rock and the loading method. The load corresponding to the maximal incubation degree in the fracture process is very closer to the plastic yield point load, about 92.19%-95.47% of the peak load. The inoculation and development process of the micro-cracks of the specimen crack tips during loading is reflected by the acoustic emission signals, and the length of the specimen fracture process zone determined by the acoustic emission positioning point has good consistency with DICM. The research work is helpful to understand in depth the inoculation law of rock fracture process zones. © 2021, Science Press. All right reserved.

引用

页码：290 / 301

页数：11

共 29 条

[1]

ZHAO Yixin, GONG Shuang, JIANG Yaodong, Et al., Characteristics of tensile strength and fracture properties of coal based on semi-circular bending tests, Chinese Journal of Rock Mechanics and Engineering, 35, 6, pp. 1255-1264, (2016)

[2]

YANG Yongming, JU Yang, CHEN Jialiang, Distribution properties of stress and cracks propagation behavior of porous rocks during splitting, Journal of China Coal Society, 39, 4, pp. 658-665, (2014)

[3]

HENG Shuai, LI Xianzhong, LIU Xiao, Et al., Study on the propagation mechanisms of shale fractures under direct shear conditions, Chinese Journal of Rock Mechanics and Engineering, 38, 12, pp. 2438-2450, (2019)

[4]

DING Xin, XIAO Xiaochun, LU Xiangfeng, Et al., Characteristics and evolution mechanism of acoustic emission time-frequency signal during coal failure process, Journal of China Coal Society, 44, 10, pp. 2999-3011, (2019)

[5]

MA Liqiang, ZHANG Yao, SUN Hai, Et al., Experimental study on dependence of infrared radiation on stress for coal fracturing process, Journal of China Coal Society, 42, 1, pp. 140-147, (2017)

[6]

KURUPPU M D, OBARA Y, AYATOLLAHI M R, Et al., ISRM-suggested method for determining the mode I static fracture toughness using semi-circular bend specimen, Rock Mechanics and Rock Engineering, 47, 1, pp. 267-274, (2014)

[7]

OUCHTERLONY F., Suggested methods for determining the fracture toughness of rock = Méthodes proposées pour déterminer la résistance des roches aux fractures, International Journal of Rock Mechanics and Mining Sciences and Geomechanics Abstracts, 25, 2, pp. 71-96, (1988)

[8]

FOWELL R J., Suggested method for determining mode I fracture toughness using Cracked Chevron Notched Brazilian Disc(CCNBD) specimens, International Journal of Rock Mechanics and Mining Sciences and Geomechanics Abstracts, 32, 1, pp. 57-64, (1995)

[9]

TANG T X, BAZANT Z P, YANG S, Et al., Variable-notch one-size test method for fracture energy and process zone length, Engineering Fracture Mechanics, 55, 3, pp. 383-404, (1996)

[10]

WANG Qizhi, WU Lizhou, Determination of elastic modulus, tensile strength and fracture toughness of britle rocks by using flattened Brazilian disk specimen-part II: experimental results, Chinese Journal of Rock Mechanics and Engineering, 23, 2, pp. 199-204, (2004)

← 1 2 3 →