摘要
通过对变粒岩、花岗岩、石灰岩、粉砂岩等四种岩石进行室内单轴加载声发射试验,获取岩石破裂全过程的应力-应变曲线、声发射参数及声发射信号。根据岩石破裂过程,从时、频域对声发射信号进行分析,着重对比了不同岩石的力学性质、声发射信号频域特征。研究结果表明:采用声发射率、能率可以很好地描述岩石破裂损伤的整个阶段;随着加载的进行,根据岩体变形及破裂程度的不同,不同岩石破裂阶段的声发射信号的频带范围也在不断发生变化。结合声发射时间序列参数特征和频谱特性,可得出岩石破裂时的损伤特性,为现场岩体的稳定性监测提供技术支持。
Time frequency characteristics of AE(acoustic emission) serials of different types of rocks were investigated by uniaxial compression test. The complete stress-strain curves,the AE characteristics and the fracture patterns of rocks were obtained. According to the destruction of rock specimens,the acoustic emission signals were analyzed in time and frequency domain. Different mechanical properties,the AE signal frequency domain feature of different rocks were researched. The results show that the AE rates and AE energy rates can be fit for the rock rupture.During the loading,in different rock rupture phase the acoustic emission signal frequency band range also change with the deformation and rupture levels of different rock mass. Combined with the AE time series parameters and spectrum characteristics,the rupture of rock damage feature can be acquired. The time frequency characteristics of AE can be regarded as the technical support to the rock mass stability monitoring.
出处
《地下空间与工程学报》
CSCD
北大核心
2014年第4期776-782,共7页
Chinese Journal of Underground Space and Engineering
基金
国家自然科学基金资助项目(51174071
51374088)
河北省高等学校科学研究计划项目(QN2014067)
河北联合大学青年基金资助项目(z201203)
关键词
声发射
时域
频域
小波能谱系数
acoustic emission(AE)
time domain
frequency domain
wavelet energy spectrum coefficient