TIME-DELAY ESTIMATION OF ACOUSTIC EMISSION SIGNALS OF ROCK USING TIME-FREQUENCY ENERGY ANALYSIS BASED ON WAVELET TRANSFORM
KANG Yumei1，ZHU Wancheng1，BAI Quan2，XIE Linmao1，TANG Chun¢an3
(1. College of Resources and Civil Engineering，Northeastern University，Shenyang，Liaoning 110004，China； 2. School of Architecture and Civil Engineering，Shenyang University of Technology，Shenyang，Liaoning 110870，China； 3. School of Civil and Hydraulic Engineering，Dalian University of Technology，Dalian，Liaoning 116024，China)
Abstract：Since acoustic emission(AE) source location is based on the time delays of AE signals received at each sensor，the accuracy of AE source location is directly affected by the time-delay estimation of AE signals. First，based on the recognition of the waveform and frequency of AE signals using wavelet transform；the waveforms with a single(or very narrow band) frequency，which are related to AE wave with different damages，are extracted and used to estimate the time delays of the AE signals among sensors；thus a more scientific method for AE source location based on wavelet transform is established. Then，the AE signals during the failure process of rock specimen under uniaxial compression are monitored by using Hyperion AE system，and the AE sources are located by using the common arithmetic provided by this AE system. Finally，the wavelet transform-based method is employed to locate the AE source based on the time delays of AE signals estimated according to the time-frequency energy analyses of AE signals. Comparisons between this new AE source location results with those obtained from Hyperion AE system indicate that the errors of AE source location can be effectively diminished；thus it can enhance the precision for damage detection in rocks.
康玉梅，朱万成，白泉，谢林茂，唐春安. 基于小波变换时频能量分析技术的岩石声发射信号时延估计[J]. 岩石力学与工程学报, 2010, 29(05): 1010-1016.
KANG Yumei1，ZHU Wancheng1，BAI Quan2，XIE Linmao1，TANG Chun¢an3. TIME-DELAY ESTIMATION OF ACOUSTIC EMISSION SIGNALS OF ROCK USING TIME-FREQUENCY ENERGY ANALYSIS BASED ON WAVELET TRANSFORM. , 2010, 29(05): 1010-1016.
