Understanding rock behavior is crucial in mine geotechnical engineering to ensure construction efficiency,mitigate rock-related hazards,and promote environmental sustainability.Coda Wave Interferometry(CWI),a non-dest...Understanding rock behavior is crucial in mine geotechnical engineering to ensure construction efficiency,mitigate rock-related hazards,and promote environmental sustainability.Coda Wave Interferometry(CWI),a non-destructive ultrasonic testing method,has been widely employed to assess micro-damage evolution in rocks induced by perturbations in scatterer position,velocity,or source location due to its exceptional sensitivity.However,challenges persist in evaluating cross-scale rock behavior influenced by nonlinear deformation and multi-field interactions under multiple coupled perturbations.A comprehensive review of the perturbation factors affecting rock damage evolution and potential failure mechanisms is essential for presenting available knowledge in a more systematic and structured manner.This review provides an in-depth analysis of the CWI technique,encompassing its origins,theoretical framework,and classical data processing methodologies.Additionally,it explores the diverse applications of CWI in assessing rock behavior under various perturbation factors,including temperature variations,fluid infiltration,and stress conditions,with a particular emphasis on nonlinear deformation and multi-field coupling effects.Furthermore,a novel method for calculating relative velocity changes in coda waves is introduced,enabling a more precise characterization of the entire rock failure process.The study also proposes a cutting-edge concept of ultra-early and refined monitoring and warning technology for mine rock disasters,leveraging the advancements in CWI.Finally,the review highlights the potential future developments of CWI in high-level intelligent mining scenarios,particularly its integration with ambient noise interferometry and microseismic coda wave analysis.This work serves as a valuable reference,contributing to the refinement of CWI applications for assessing complex rock behavior and enhancing the accuracy of rock disaster prediction and early warning systems.展开更多
A filed experiment was conducted continuously for three days,and the velocity variation was measured using coda wave interferometry.The measurement error is estimated to be around 10-4,which coincides well with the th...A filed experiment was conducted continuously for three days,and the velocity variation was measured using coda wave interferometry.The measurement error is estimated to be around 10-4,which coincides well with the theoretical error.The velocity variation during this period is up to 10-3.The relationship between velocity variation and changes in air temperature,barometric pressure and solid earth tide was analyzed with linear least square fitting.The velocity has no dependence on air temperature,but displayed change of the order of 10-6～10-7 when the barometer or earth tide changed one Pa.展开更多
Multiply scattered waves are sensitive to media changes owing to the effect of repeated sampling,superposition and amplification. Based on this characteristic,small-medium changes could be detected by using coda wave ...Multiply scattered waves are sensitive to media changes owing to the effect of repeated sampling,superposition and amplification. Based on this characteristic,small-medium changes could be detected by using coda wave interferometry. In recent years,coda wave interferometry has been widely used in estimating velocity variation with high precision in areas such as seismology and non-destructive testing. This paper systematically presents the principle and research status of coda wave interferometry,and especial focus is placed on the research of media velocity variations by using repeating earthquakes,artificial sources,and ambient noise. Applications of coda wave interferometry can contribute to the more subtle understanding of dynamic evolution process in the medium.展开更多
We conducted a long-term monitoring experiment on the Lutuanxilu Bridge located in Changping District of Beijing, employing our recently developed real-time bridge monitoring system based on the Guralp CMG-6TD broadba...We conducted a long-term monitoring experiment on the Lutuanxilu Bridge located in Changping District of Beijing, employing our recently developed real-time bridge monitoring system based on the Guralp CMG-6TD broadband seismometer. We identified the modal parameters with the stochastic subspace identification( SSI) algorithm,and continuously monitored the temporal velocity variation with coda wave interferometry.The results show that:( 1) the highly sensitive Guralp CMG-6TD broadband seismometer,which records the three-component vibration signal within broad frequency range,is well suited for long-term bridge health monitoring.( 2) With the continuous vibration signal from ambient excitation,the stochastic subspace algorithm can robustly identify the low-order modal parameters and the coda wave interferometry can accurately monitor the tiny velocity variation.( 3) The elastic modulus of bridge materials changes significantly associated with varying temperature,leading to diurnal velocity variation with amplitude of approximately 1%. The velocity variation shows strong negative correlation with temperature fluctuation. Meanwhile,the modal frequencies remain quite stable,suggesting that the velocity variation may be a more sensitive quantitative damage index.( 4) While the modal frequencies reflect the integrated health status of the bridge,the velocity variation can be utilized to monitor the local elastic modulus. Therefore,it is crucial for bridge health monitoring to continuously monitor the two key damage indexes under ambient excitation.展开更多
基金supported by the National Key Research and Development Program of China(Fund for Young Scientists 2021YFC2900400)Chongqing Outstanding Youth Science Fund project(CSTB2023NSCQ-JQX0027).
文摘Understanding rock behavior is crucial in mine geotechnical engineering to ensure construction efficiency,mitigate rock-related hazards,and promote environmental sustainability.Coda Wave Interferometry(CWI),a non-destructive ultrasonic testing method,has been widely employed to assess micro-damage evolution in rocks induced by perturbations in scatterer position,velocity,or source location due to its exceptional sensitivity.However,challenges persist in evaluating cross-scale rock behavior influenced by nonlinear deformation and multi-field interactions under multiple coupled perturbations.A comprehensive review of the perturbation factors affecting rock damage evolution and potential failure mechanisms is essential for presenting available knowledge in a more systematic and structured manner.This review provides an in-depth analysis of the CWI technique,encompassing its origins,theoretical framework,and classical data processing methodologies.Additionally,it explores the diverse applications of CWI in assessing rock behavior under various perturbation factors,including temperature variations,fluid infiltration,and stress conditions,with a particular emphasis on nonlinear deformation and multi-field coupling effects.Furthermore,a novel method for calculating relative velocity changes in coda waves is introduced,enabling a more precise characterization of the entire rock failure process.The study also proposes a cutting-edge concept of ultra-early and refined monitoring and warning technology for mine rock disasters,leveraging the advancements in CWI.Finally,the review highlights the potential future developments of CWI in high-level intelligent mining scenarios,particularly its integration with ambient noise interferometry and microseismic coda wave analysis.This work serves as a valuable reference,contributing to the refinement of CWI applications for assessing complex rock behavior and enhancing the accuracy of rock disaster prediction and early warning systems.
基金sponsored by the Special R & D Project of China Earthquake Administration(200808002)the Special Project of Basic Scientific Research of the Institute of Geophysics,CEA(DQJB08B13)
文摘A filed experiment was conducted continuously for three days,and the velocity variation was measured using coda wave interferometry.The measurement error is estimated to be around 10-4,which coincides well with the theoretical error.The velocity variation during this period is up to 10-3.The relationship between velocity variation and changes in air temperature,barometric pressure and solid earth tide was analyzed with linear least square fitting.The velocity has no dependence on air temperature,but displayed change of the order of 10-6～10-7 when the barometer or earth tide changed one Pa.
基金sponsored by the Task of Department of Earthquake Monitoring and Prediction,CEAthe Special Fund of Earthquake Scientific Research of China Earthquake Administration(201208003)
文摘Multiply scattered waves are sensitive to media changes owing to the effect of repeated sampling,superposition and amplification. Based on this characteristic,small-medium changes could be detected by using coda wave interferometry. In recent years,coda wave interferometry has been widely used in estimating velocity variation with high precision in areas such as seismology and non-destructive testing. This paper systematically presents the principle and research status of coda wave interferometry,and especial focus is placed on the research of media velocity variations by using repeating earthquakes,artificial sources,and ambient noise. Applications of coda wave interferometry can contribute to the more subtle understanding of dynamic evolution process in the medium.
基金sponsored by "Microseismic response characteristic of typical bridges in Beijing under environmental excitations"( ZX20130335)the scientific research foundation of China University of Petroleum-Beijing ( 2462014YJRC045)
文摘We conducted a long-term monitoring experiment on the Lutuanxilu Bridge located in Changping District of Beijing, employing our recently developed real-time bridge monitoring system based on the Guralp CMG-6TD broadband seismometer. We identified the modal parameters with the stochastic subspace identification( SSI) algorithm,and continuously monitored the temporal velocity variation with coda wave interferometry.The results show that:( 1) the highly sensitive Guralp CMG-6TD broadband seismometer,which records the three-component vibration signal within broad frequency range,is well suited for long-term bridge health monitoring.( 2) With the continuous vibration signal from ambient excitation,the stochastic subspace algorithm can robustly identify the low-order modal parameters and the coda wave interferometry can accurately monitor the tiny velocity variation.( 3) The elastic modulus of bridge materials changes significantly associated with varying temperature,leading to diurnal velocity variation with amplitude of approximately 1%. The velocity variation shows strong negative correlation with temperature fluctuation. Meanwhile,the modal frequencies remain quite stable,suggesting that the velocity variation may be a more sensitive quantitative damage index.( 4) While the modal frequencies reflect the integrated health status of the bridge,the velocity variation can be utilized to monitor the local elastic modulus. Therefore,it is crucial for bridge health monitoring to continuously monitor the two key damage indexes under ambient excitation.
