基于声发射时频特性的花岗岩各向异性实验研究  

Research on the anisotropy of granite based on the characteristics of time-frequency by acoustic emission

作　　者：游勋[1] 王春仁[1] 吕欣 赵迎贵[1] 余敏[1] YOU Xun;WANG Chunren;LYU Xin;ZHAO Yinggui;YU Min(Design&Research Institute of Masteel Engineering Technology Group Co.,Ltd.,Maanshan 243000,China;Modern Technology and Education Center,North China University of Science and Technology,Tangshan 063210,China)

机构地区：[1]马钢集团设计研究院有限责任公司,安徽马鞍山243000 [2]华北理工大学现代技术教育中心,河北唐山063210

出　　处：《中国矿业》2020年第9期152-159,共8页China Mining Magazine

基　　金：河北省科技计划项目资助(编号:15273908)。

摘　　要：为了更好地将声发射/微震等手段应用于岩石破裂监测,为工程岩体的稳定性评判提供技术依据,考虑到岩石材料所固有的各向异性等属性,本文拟从声发射监测角度探究岩石各向异性,通过对花岗岩进行水平卸荷破坏试验,开展材料各向异性和应力各向异性对声发射时影响研究。结果表明,各向异性(包括材料各向异性和应力各向异性)是引起不同位置声发射时频域差异性的主要原因,偏应力的存在是岩石出现应力各向异性的重要原因。加载初期以材料各向异性为主,随着损伤破裂的发展,应力各向异性开始占主导作用。声发射时域中绝对能量受材料各向异性的影响较大,幅值受应力各向异性的影响更为显著。声发射频域中不同频段的主频分量对材料各向异性和应力各向异性的敏感程度不同,低频(约20 kHz)在试验初期受材料各向异性影响,试验后期由应力各向异性所控制;中频(40~50 kHz)不受各向异性的影响,在整个阶段均有较高的响应;次高频(50~60 kHz)受应力各向异性和材料各向异性的共同影响;高频(80~110 kHz)对应力各向异性的表现较为敏感。In order to apply AE/microseism to rock fracture monitoring,providing technical basis for the evaluation of the stability of engineering rock mass,by considering the rock properties such as anisotropy inherent.The horizontal unloading test of granite is studied,the characteristic of stress-anisotropy and material-anisotropy have been taking a discussion from the time-frequency of acoustic emission(AE).The results show that the reason of different characteristics of AE time-frequency in different location is the anisotropy,and the existence of deviatoric stress can caused stress-anisotropy.At the beginning of test,the material-anisotropy takes the main factor,and the stress-anisotropy will bring a main reaction because of the rupture development.In the time-domain,the AE absolute energy takes more affected by material-anisotropy,and amplitude is influences by stress-anisotropy.In the frequency-domain,the characteristic of stress-anisotropy and material-anisotropy has not take the same effects from the different frequency band of random frequency.The lowly-frequency(about 20 kHz)is effect by material-anisotropy at the beginning of experiment,and it changed to stress-anisotropy during the lateral of experiment.The intermediately-frequency(40-50 kHz)is not affected by the material-anisotropy or stress-anisotropy.The second highly-frequency(50-60 kHz)is influence upon both of the material-anisotropy and stress-anisotropy.The highly-frequency(80-110 kHz)is more sensitive on stress anisotropy.

关 键 词：岩石破裂 声发射 材料各向异性 应力各向异性 

分 类 号：TU45[建筑科学—岩土工程]