ACOUSTIC EMISSION CHARACTERISTICS OF FRACTURED ROCKS DURING CREEP SHEAR
WANG Yuxi1,WANG Jin?an1,2,TANG Jun1
(1. School of Civil and Environmental Engineering,University of Science and Technology Beijing,Beijing 100083,China;
2. State Key Laboratory of High-efficient Mining and Safety of Metal Mines,Ministry of Education,University of Science and Technology Beijing,Beijing 100083,China)
Abstract:Under a long-term geomechanical loading,creep deformation would occur in fractured rocks,accompanying with acoustic emission(AE). The laws of AE are meaningful to monitor and warning of the rock in stability. In order to look into the AE features of fractured rocks during creep shear,the direct creep shear experiment of fractured rocks induced by compressive shear and Brazilian tension was carried out under constant normal force. AE technology was used to detect the acoustic events during the creep shear. The relationship between AE energy and creep shear displacement at different loading stages is revealed. Meanwhile,the locations of the interlocks and the micro-contact fractures are also identified the laser scanned contour maps of the fractured rock surfaces by the AE events. The experiment shows that there is a signal blank phenomenon of AE events before the instability occurs. Regarding to the fractured rocks induced by Brazilian tension,the peak of AE energy mainly appears at the middle and late stages of the creep shear process,and AE energy reaches local maximum at the early stage of each loading followed with its downward trend;for the fractured rocks induced by compressive shear,AE energy valley appears at the middle stage of the creep shear process,and at each shear loading a small peak of AE energy appears at the middle stage. In addition,AE position detection shows that the micro-contact fractures mainly occur first at the central part of the interlocked surfaces. The initial micro-contact fractures present a directional character that a zonal distribution develops perpendicular to the shear direction at early loading stages.
赵 奎,林 颖,熊雪强. 不同应力水平下砂岩蠕变声发射频率特征研究[J]. 铜业工程,2012,(4):22-24.(ZHAO Kui,LIN Ying,XIONG Xueqiang. Studies on acoustic emission frequency of creep of sandstone under different stress levels[J]. Copper Engineering,2012,(4):22-24.(in Chinese))
Your browse does not support frame! " target="_blank">
[17]
杨更社,张全胜. 冻融环境下岩体细观损伤及水热迁移机理分析[M]. 西安:陕西科学技术出版社,2005:38.(YANG Gengshe,ZHANG Quansheng. Analysis for mechanism of rock microscopic damage and moisture-heat transfer under the frost and thaw condition[M]. Xi′an:Shaanxi Science and Technology Press,2005:38.(in Chinese))
Your browse does not support frame! " target="_blank">
[1]
杜守继,朱建栋,职洪涛. 岩石节理经历不同变形历史的剪切试验研究[J]. 岩石力学与工程学报,2006,25(1):57-60.(DU Shouji,ZHU Jiandong,ZHI Hongtao. Shear tests on rock joints under different shear deformation histories[J]. Chinese Journal of Rock Mechanics and Engineering,2006,25(1):57-60.(in Chinese))
Your browse does not support frame! " target="_blank">
KISHIDA K,KAWAGUCHI Y,NAKASHIMA S,et al. Estimation of shear strength recovery and permeability of single rock fractures in shear-hold-shear type direct shear tests[J]. International Journal of Rock Mechanics and Mining Sciences,2011,48(5):782-793.
[9]
THOMPSON B D,YOUNG R P,LOCKNER D A. Premonitory acoustic emissions and stick-slip in natural and smooth-faulted Westerly granite[J]. Journal of Geophysical Research,2009,114(B2):B02205.
Your browse does not support frame! " target="_blank">
[11]
腾山邦久. 声发射(AE)技术的应用[M]. 冯夏庭译. 北京:冶金工业出版社,1996:10-285.(TENGSHAN B. Application of acoustic emission(AE) technology[M]. Translated by FENG Xiating. Beijing:Metallurgical Industry Press,1996:10-285.(in Chinese))
Your browse does not support frame! " target="_blank">
[14]
WANG R B,XU W Y,ZHANG J C,et al. Study on accelerated creep properties and creep damage constitutive relation for volcanic breccias[J]. Springer Series in Geomehanics and Geoengineering,2013:633-639.
Your browse does not support frame! " target="_blank">
[2]
王金安,李 飞,曹秋菊,等. 断裂岩石蠕剪中的细观接触损伤试验研究[J]. 岩土力学,2013,34(12):3 345-3 383.(WANG Jin?an,LI Fei,CAO Qiuju,et al. Experimental study of the meso-contact damage of fractured rocks in creep shear[J]. Rock and Soil Mechanics,2013,34(12):3 345-3 383.(in Chinese))
Your browse does not support frame! " target="_blank">
[3]
王洪涛,郑师春. 福建第四纪活断裂岩石显微构造特征与孕震标志研究[J]. 华南地震,2011,31(2):1-12.(WANG Hongtao,ZHENG Shichun. Quaternary active faults of rock microscopic structure characteristics and earthquake research of Fujian[J]. South China Journal of Seismology,2011,31(2):1-12.(in Chinese))
Your browse does not support frame! " target="_blank">
[5]
ZHAO Y L,WAN W,WANG W J,et al. Compressive-shear rheological fracture of rock-like cracks and subcritical crack propagation test and fracture mechanism[J]. Chinese Journal of Geotechnical Engineering,2012,34(6):1 050-1 059.
Your browse does not support frame! " target="_blank">
[6]
KEMENY J M,TANG F F. Numerical damage model for rock based on microcrack growth,interaction,and coalescence[J]. Damage Mechanics in Engineering Materials,1990,(109):103-116.
Your browse does not support frame! " target="_blank">
[8]
XU T,XU Q,TANG C A,et al. The evolution of rock failure with discontinuities due to shear creep[J]. Acta Geotechnica,2013,8(6):567-581.
[10]
纪洪广. 混凝土材料声发射性能研究与应用[M]. 北京:煤炭工业出版社,2003:1.(JI Hongguang. Research and application of the acoustic emission performance of concrete material[M]. Beijing:China Coal Industry Publishing House,2003:1.(in Chinese))
Your browse does not support frame! " target="_blank">
[12]
STEAD D,SZCZEPANIK Z. Time-dependent acoustic emission studies on potash[C]// Proceedings of the 32nd U.S. Symposium on Rock Mechanics(USRMS). Virginia:American Rock Mechanics Association,1991:471-479.
Your browse does not support frame! " target="_blank">
[13]
赵兴东,李元辉,袁瑞甫,等. 基于声发射定位的岩石裂纹动态演化过程研究[J]. 岩石力学与工程学报,2007,26(5):944-950.(ZHAO Xingdong,LI Yuanhui,YUAN Ruifu. Study on crack dynamic propagation process of rock samples based on acoustic emission location[J]. Chinese Journal of Rock Mechanics and Engineering,2007,26(5):944-950.(in Chinese))
[16]
曹树刚,刘延保,张立强,等. 突出煤体单轴压缩和蠕变状态下的声发射对比试验[J]. 煤炭学报,2007,32(12):1 264-1 268.(CAO Shugang,LIU Yanbao,ZHANG Liqiang,et al. Experimental on acoustic emission of outburst-hazardous coal under uniaxial compression and creep[J]. Journal of China Coal Society,2007,32(12):1 264- 1 268.(in Chinese))
Your browse does not support frame! " target="_blank">
李地元,李夕兵,LI C Charlie. 2 种岩石直接拉压作用下的力学性能试验研究[J]. 岩石力学与工程学报,2010,29(3):624-632.(LI Diyuan,LI Xibing,LI C Charlie. Experimental studies of mechanical properties of two rocks under direct compression and tension[J]. Chinese Journal of Rock Mechanics and Engineering,2010,29(3):624-632.(in Chinese))