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Distributed fiber optic sensors for tunnel monitoring:A state-of-the-art review
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作者 Xuehui Zhang Honghu Zhu +1 位作者 Xi Jiang Wout Broere 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第9期3841-3863,共23页
Distributed fiber optic sensors(DFOSs)possess the capability to measure strain and temperature variations over long distances,demonstrating outstanding potential for monitoring underground infrastructure.This study pr... Distributed fiber optic sensors(DFOSs)possess the capability to measure strain and temperature variations over long distances,demonstrating outstanding potential for monitoring underground infrastructure.This study presents a state-of-the-art review of the DFOS applications for monitoring and assessing the deformation behavior of typical tunnel infrastructure,including bored tunnels,conventional tunnels,as well as immersed and cut-and-cover tunnels.DFOS systems based on Brillouin and Rayleigh scattering principles are both considered.When implementing DFOS monitoring,the fiber optic cable can be primarily installed along transverse and longitudinal directions to(1)measure distributed strains by continuously adhering the fiber to the structure’s surface or embedding it in the lining,or(2)measure point displacements by spot-anchoring it on the lining surface.There are four critical aspects of DFOS monitoring,including proper selection of the sensing fiber,selection of the measuring principle for the specific application,design of an effective sensor layout,and establishment of robust field sensor instrumentation.These four issues are comprehensively discussed,and practical suggestions are provided for the implementation of DFOS in tunnel infrastructure monitoring. 展开更多
关键词 distributed fiber optic sensor(DFOS) Tunnel infrastructure distributed strain sensing Point displacement monitoring Field instrumentation
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FIBER OPTIC TEMPERATURE MEASURING SYSTEM
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作者 马乃兵 骆飞 +1 位作者 孟爱东 杨春 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 1998年第2期34-38,共5页
This paper presents a fiber optic temperature measuring system used for measuring the temperature in many occasions. The system is of reflective type and composed of thermostatic bimetal plate, lever piston framewo... This paper presents a fiber optic temperature measuring system used for measuring the temperature in many occasions. The system is of reflective type and composed of thermostatic bimetal plate, lever piston framework, optical grating and optical fiber probes. When the temperature changes, the thermostatic bimetal plate deforms. Through lever piston framework, the optical grating produces displacement in the upright direction. Thus the change of the temperature is transformed into the upright displacement of the optical grating. Optical fiber probes are used for detecting the number of streak lines of the optical grating′s displacement depending on the change of temperature. The detected signal can be transmitted to the control center through optical fiber cable up to distance of 1 km. The measurable range of this system reaches 100℃ with accuracy of ±0.2℃. 展开更多
关键词 optical fibers sensorS temperatureS thermostatic bimetal plates optical gratings
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Network Integration of Distributed Optical Fiber Temperature Sensor
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作者 Gui-Yan Li Hong-Lin Liu Zai-Xuan Zhang 《Journal of Electronic Science and Technology of China》 2008年第4期399-401,共3页
The integration of distributed optical fiber temperature sensor with supervisory control and data acquisition (SCADA) system is proposed and implemented. In the implementation of the integration, both the compatibil... The integration of distributed optical fiber temperature sensor with supervisory control and data acquisition (SCADA) system is proposed and implemented. In the implementation of the integration, both the compatibility with traditional system and the characteristics of distributed optical fiber temperature sensor is considered before Modbus TCP/IP protocol is chosen. The protocol is implemented with open source component Indy. The Modbus TCP/IP protocol used in the system is proved to be fast and robust. 展开更多
关键词 distributed optical fiber temperature sensor Modbus TCP/IP supervisory control and dataacquisition (SCADA).
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Practical Pattern Recognition System for Distributed Optical Fiber Intrusion Monitoring Based on Ф-COTDR 被引量:4
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作者 CAO Cong FAN Xinyu +1 位作者 LIU Qingwen HE Zuyuan 《ZTE Communications》 2017年第3期52-55,共4页
At present, the demand for perimeter security system is in-creasing greatly, especially for such system based on distribut-ed optical fiber sensing. This paper proposes a perimeter se-curity monitoring system based on... At present, the demand for perimeter security system is in-creasing greatly, especially for such system based on distribut-ed optical fiber sensing. This paper proposes a perimeter se-curity monitoring system based on phase-sensitive coherentoptical time domain reflectometry(Ф-COTDR) with the practi-cal pattern recognition function. We use fast Fourier trans-form(FFT) to exact features from intrusion events and a multi-class classification algorithm derived from support vector ma-chine(SVM) to work as a pattern recognition technique. Fivedifferent types of events are classified by using a classifica-tion algorithm based on SVM through a three-dimensional fea-ture vector. Moreover, the identification results of the patternrecognition system show that an identification accurate rate of92.62% on average can be achieved. 展开更多
关键词 fiber optics sensors COTDR distributed vibration sensing SVM pattern recognition
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Distributed optical fiber acoustic sensor for in situ monitoring of marine natural gas hydrates production for the first time in the Shenhu Area,China 被引量:2
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作者 Xiang-ge He Xue-min Wu +6 位作者 Lei Wang Qian-yong Liang Li-juan Gu Fei Liu Hai-long Lu Yi Zhang Min Zhang 《China Geology》 2022年第2期322-329,共8页
The distributed acoustic sensor(DAS)uses a single optical cable as the sensing unit,which can capture the acoustic and vibration signals along the optical cable in real-time.So it is suitable for monitoring downhole p... The distributed acoustic sensor(DAS)uses a single optical cable as the sensing unit,which can capture the acoustic and vibration signals along the optical cable in real-time.So it is suitable for monitoring downhole production activities in the process of oil and gas development.The authors applied the DAS system in a gas production well in the South China Sea for in situ monitoring of the whole wellbore for the first time and obtained the distributed acoustic signals along the whole wellbore.These signals can clearly distinguish the vertical section,curve section,and horizontal production section.The collected acoustic signal with the frequency of approximately 50 Hz caused by the electric submersible pump exhibit a signal-to-noise ratio higher than 27 dB.By analyzing the acoustic signals in the production section,it can be located the layers with high gas production rates.Once an accurate physical model is built in the future,the gas production profile will be obtained.In addition,the DAS system can track the trajectory of downhole tools in the wellbore to guide the operation.Through the velocity analysis of the typical signals,the type of fluids in the wellbore can be distinguished.The successful application of the system provides a promising whole wellbore acoustic monitoring tool for the production of marine gas hydrate,with a good application prospect. 展开更多
关键词 Gas hydrate production monitoring optical fiber sensor distributed acoustic sensor In situ monitoring Fluid type NGHs exploration trial engineering Oil and gas exploration engineering Shenhu Area South China Sea
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Highly sensitive optical fiber temperature sensor based on resonance in sidewall of liquid-filled silica capillary tube
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作者 Min Li Biao Feng Jiwen Yin 《Chinese Physics B》 SCIE EI CAS CSCD 2019年第11期156-160,共5页
A highly sensitive optical fiber temperature sensor based on a section of liquid-filled silica capillary tube(SCT)between single mode fibers is proposed. Two micro-holes are drilled on two sides of SCT directly by usi... A highly sensitive optical fiber temperature sensor based on a section of liquid-filled silica capillary tube(SCT)between single mode fibers is proposed. Two micro-holes are drilled on two sides of SCT directly by using femtosecond laser micromachining, and liquid polymer is filled into the SCT through the micro-holes without any air bubbles and then sealed by using ultra-violet(UV) cure adhesive. The sidewall of the SCT forms a Fabry–Perot resonator, and loss peaks are achieved in the transmission spectrum of the SCT at the resonant wavelength. The resonance condition can be influenced by the refractive index variation of the liquid polymer filled in SCT, which is sensitive to temperature due to its high thermooptical coefficient(-2.98 × 10^-4℃^-1). The experimental result shows that the temperature sensitivity of the proposed fiber structure reaches 5.09 nm/℃ with a perfect linearity of 99.8%. In addition, it exhibits good repeatability and reliability in temperature sensing application. 展开更多
关键词 optical fiber sensors LIQUID FILLING temperature measurement
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A Nonlinear Mirror Structure to Improve the Performance of the Distributed Fiber Temperature Sensor Based on Raman Backscattering 被引量:1
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作者 Yang Chen Yong Liu Xiao-Li Zhou Li-Xun Zhang Zhi-Yong Dai Yong-Zhi Liu 《Journal of Electronic Science and Technology of China》 2008年第4期405-407,共3页
A novel nonlinear mirror structure which can increase the optical signal-to-noise ratio of a distributed fiber Raman temperature sensor is proposed, and 6 dB improvement of the optical signal-to-noise ratio is obtaine... A novel nonlinear mirror structure which can increase the optical signal-to-noise ratio of a distributed fiber Raman temperature sensor is proposed, and 6 dB improvement of the optical signal-to-noise ratio is obtained. With the assistance of the nonlinear mirror, we demonstrate that the spatial resolution of the sensor is improved from 3 m to 1 m, and the temperature accuracy is improved from ±0.6℃ to ±0.2℃. The theoretical analysis and the experimental data are in good agreement. 展开更多
关键词 distributed Sensing fiber sensing nonlinear mirror Raman baekscattering temperature sensor.
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Mathematical Model of Fiber Optic Temperature Sensor Based on Optic Absorption and Experiment Testing
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作者 HU Yan-ling (Yanshan University, Qihuangdao 066004, CHN) 《Semiconductor Photonics and Technology》 CAS 2001年第1期60-64,共5页
On the basis of analysis on the temperature monitoring methods for high voltage devices, a new type of fiber optic sensor structure with reference channel is given. And the operation principle of fiber optic sensor is... On the basis of analysis on the temperature monitoring methods for high voltage devices, a new type of fiber optic sensor structure with reference channel is given. And the operation principle of fiber optic sensor is analysed at large based on the absorption of semiconductor chip. The mathematical model of both devices and the whole system are also given. It is proved by the experiment that this mathematical model is reliable. 展开更多
关键词 fiber optic temperature sensor optic absorption reference channel Mathematical model
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DISTRIBUTED MICROBEND FIBER-OPTIC STRAIN SENSOR
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作者 孟爱东 骆飞 袁慎芳 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2000年第2期224-227,共4页
The distributed strain sensor has significant application in real time measurement of strain status for large and important engineering structures such as aircraft, bridge and dam. In this paper, a quasi distributed... The distributed strain sensor has significant application in real time measurement of strain status for large and important engineering structures such as aircraft, bridge and dam. In this paper, a quasi distributed optical fiber strain sensor system is set up using optical time domain reflect technique. The local strain sensors based on a novel microbend configuration are designed and applied to measure local strains along the optical fiber. As the result of the experimental research, the microbend sensors show high sensitivity, good linearity and repeatability in certain operation range. 展开更多
关键词 strain measurement strain sensor optical fiber sensor distributed micro bend
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Distributed Fiber Optic Monitoring and Stability Analysis of a Model Slope under Surcharge Loading 被引量:23
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作者 ZHU Hong-Hu SHI Bin +2 位作者 ZHANG Jie YAN Jun-Fan ZHANG Cheng-Cheng 《Journal of Mountain Science》 SCIE CSCD 2014年第4期979-989,共11页
In the discipline of geotechnical engineering, fiber optic sensor based distributed monitoring has played an increasingly important role over the past few decades. Compared with conventional sensors, fiber optic senso... In the discipline of geotechnical engineering, fiber optic sensor based distributed monitoring has played an increasingly important role over the past few decades. Compared with conventional sensors, fiber optic sensors have a variety of exclusive advantages, such as smaller size, higher precision, and better corrosion resistance. These innovative monitoring technologies have been successfully applied for performance monitoring of geo-structures and early warning of potential geo- hazards around the world. In order to investigate their ability to monitor slope stability problems, a medium-sized model of soil nailed slope has been constructed in laboratory. The fully distributed Brillouin optical time-domain analysis (BOTDA) sensing technology was employed to measure the horizontal strain distributions inside the model slope. During model construction, a specially designed strain sensing fiber was buried in the soil mass. Afterward, the surcharge loading was applied on the slope crest in stages using hydraulic jacks and a reaction frame. During testing, an NBX-6o5o BOTDA sensing interrogator was used to collect the fiber optic sensing data. The test results have been analyzed in detail, which shows that the fiber optic sensors can capture the progressive deformation and failure pattern of the model slope. The limit equilibrium analyses were also conducted to obtain the factors ofsafety of the slope under different surface loadings. It is found that the characteristic maximum strains can reflect the stability of the model slope and an empirical relationship was obtained, This study verified the effectiveness of the distributed BOTDA sensing technology in performance monitoring of slope. 展开更多
关键词 Slope stability Geotechnical monitoring fiber optic sensor distributed strain sensing Brillouin optical time-domain analysis (BOTDA) Model test
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Flexible Optical Waveguide Bent Loss Attenuation Effects Analysis and Modeling Application to an Intrinsic Optical Fiber Temperature Sensor 被引量:3
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作者 Mustapha Remouche Francis Georges Patrick Meyrueis 《Optics and Photonics Journal》 2012年第1期1-7,共7页
The temperature dependence of the bending loss light energy in multimode optical fibers is reported and analyzed. The work described in this paper aims to extend an initial previous analysis concerning planar optical ... The temperature dependence of the bending loss light energy in multimode optical fibers is reported and analyzed. The work described in this paper aims to extend an initial previous analysis concerning planar optical waveguides, light energy loss, to circular optical waveguides. The paper also presents à novel intrinsic fiber optic sensing device base on this study allowing to measure temperatures parameters. The simulation results are validated theoretically in the case of silica/silicone optical fiber. A comparison is done between results obtained with an optical fiber and the results obtained from the previous curved optical planar waveguide study. It is showed that the bending losses and the temperature measurement range depend on the curvature radius of an optical fiber or waveguide and the kind of the optical waveguide on which the sensing process is implemented. 展开更多
关键词 optical fiber LOSSES CURVATURE sensor temperature Micro Technology
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Temperature sensor based on a single-mode tapered optical fiber 被引量:1
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作者 朱姗 邢洁雯 +1 位作者 庞拂飞 王廷云 《Journal of Shanghai University(English Edition)》 CAS 2011年第2期101-104,共4页
A temperature sensor is demonstrated and fabricated by coating the single-mode tapered optical fiber with temperature-sensitive silicone rubber. It works on the change of the evanescent fields in the tapered optical f... A temperature sensor is demonstrated and fabricated by coating the single-mode tapered optical fiber with temperature-sensitive silicone rubber. It works on the change of the evanescent fields in the tapered optical fiber. Small changes in the refractive index of coating film greatly influence the power of evanescent fields, which modulate the transmission optical power in the waist region. The range of temperature measured is from -20℃ to 70 ℃. The results show that the temperature sensor has high temperature sensitivity (0.012 mW/℃) and good repeatability. 展开更多
关键词 temperature sensor tapered optical fiber silicone rubber
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Fibre optic distributed scattering sensing system:perspectives and challenges for high performance applications 被引量:3
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作者 Marc Niklès 《仪器仪表学报》 EI CAS CSCD 北大核心 2007年第8期1345-1352,共8页
As fiber optic distributed scattering sensing systems are providing innovative solutions for the monitoring of large structures,the comparison of different techniques and solutions is difficult because of the lack of ... As fiber optic distributed scattering sensing systems are providing innovative solutions for the monitoring of large structures,the comparison of different techniques and solutions is difficult because of the lack of standardized specifications and the difficulty associated to the characterization of such systems.The article presents a tentative definition of performance specifications and qualification procedures applicable to fiber optic distributed sensing systems aiming at providing clear guidelines for their design,specifications,qualification,application and selection. 展开更多
关键词 纤维光学传感器 分布式散射传感系统 发展前景 应用 布里渊散射 空间分辨率 温度
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All-Fiber Optic Temperature Sensor
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作者 蒋雁 庞叔鸣 杨祥林 《Journal of Southeast University(English Edition)》 EI CAS 1997年第2期50-54,共5页
This paper presents a new class of all fiber optic temperature sensor, of which the heat expansion thin film is coated on the etched fiber. The sensitivity of the sensor is increased and the shape size is decreased.... This paper presents a new class of all fiber optic temperature sensor, of which the heat expansion thin film is coated on the etched fiber. The sensitivity of the sensor is increased and the shape size is decreased. This sensor possesses the linear temperature response and the good repeatability. These sensors can be used to measure finely the temperature that is lower than 200℃ with aluminium coating. 展开更多
关键词 sensor temperature opticAL fiber
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Temperature dependence of the refractive index of optical fibers
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作者 王智勇 邱琪 史双瑾 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第3期256-260,共5页
Many experimental investigations on the temperature dependence of the refractive index of optical fibers have been reported previously, however a satisfying theoretical explanation for it is still absent. In this pape... Many experimental investigations on the temperature dependence of the refractive index of optical fibers have been reported previously, however a satisfying theoretical explanation for it is still absent. In this paper, a theoretical model about the temperature dependence of the refractive index of optical fibers is presented and it is in agreement with the previous experimental results. This work is a significant reference for the research and development of temperature sensors based on optical fiber delay lines. 展开更多
关键词 refractive index optical fiber temperature sensor
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Novel Fiber Optic Temperature Sensor with Full Compensation Based on Optical Absorption
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作者 WANGJue WANGWei-min 《Semiconductor Photonics and Technology》 CAS 2000年第4期236-241,共6页
A novel system configuration of fiber optic sensor based on optical abso rption is proposed. Several compensation measures are discussed. A simulated exp eriment is designed and the output curve of system is given. Th... A novel system configuration of fiber optic sensor based on optical abso rption is proposed. Several compensation measures are discussed. A simulated exp eriment is designed and the output curve of system is given. The experiment al result shows that these compensation measures are effective on dynamic distu rbances which are caused by background light and optical fiber bend. In addition , the drifts in the light source intensity, fiber losses, and photodetector effi ciency are also compensated. 展开更多
关键词 GaAs semiconductor temperature measurement fiber optic sensor REFLECTION COMPENSATION
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Technology of fiber-optic temperature sensing and its application in & temperature measuring of gob area
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作者 LIU Jing-wen HUANG Li-ming 《Journal of Coal Science & Engineering(China)》 2011年第2期171-175,共5页
Based on advantages of technology of distributive fiber-optic temperature sensing and specific to its applications in monitoring mine conflagration, the corresponding Processes such as connection arrangement, signal t... Based on advantages of technology of distributive fiber-optic temperature sensing and specific to its applications in monitoring mine conflagration, the corresponding Processes such as connection arrangement, signal transmission and monitoring were illustrated. As applied in Sitai Coal Mine of Datong Coal Mine Group Co., this method is effective and accurate and could provide reliable gist for monitoring spontaneous combustion in gob area of mines. 展开更多
关键词 distributive optical fiber gob area temperature sensing fire source detection
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An all optical fiber gas sensor of NH3 and CO based on based on the spectral absorption and harmonic detection
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作者 Liu Jin Yang Haima +1 位作者 Yan Chaochao Song Wanqing 《International English Education Research》 2014年第12期100-103,共4页
An all optical fiber gas sensor is presented to detect the concentration of NH3 and CO. Based on the spectral absorption, The wideband light source is used to reflect two narrowband spectra by fiber grating of differe... An all optical fiber gas sensor is presented to detect the concentration of NH3 and CO. Based on the spectral absorption, The wideband light source is used to reflect two narrowband spectra by fiber grating of different duty. and piezoelectric ceramics to obtain narrowband output light. The high sensitivity detection can be measured from the second harmonic signal. The two narrowband spectra are corresponding to the absorption spectra of NH3 and CO. Concentration detection are realized by the detection of variety of light intensity. Sensitivity is proved and cost is reduced. 展开更多
关键词 DISTRIBUTION optical fiber sensor Concentration detection
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Landslide Monitoring Based on High-Resolution Distributed Fiber Optic Stress Sensor
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作者 Zhi-Yong Dai Yong Liu +3 位作者 Li-Xun Zhang Zhong-Hua Ou Ce Zhou Yong-Zhi Liu 《Journal of Electronic Science and Technology of China》 2008年第4期416-419,共4页
A landslide monitoring application is presented by using a high-resolution distributed fiber optic stress sensor. The sensor is used to monitor the intra-stress distribution and variations in landslide bodies, and can... A landslide monitoring application is presented by using a high-resolution distributed fiber optic stress sensor. The sensor is used to monitor the intra-stress distribution and variations in landslide bodies, and can be used for the early warning of the occurrence of the landslides. The principle of distributed fiber optic stress sensing and the intra-stress monitoring method for landslides are described in detail. By measuring the distributed polarization mode coupling in the polarization-maintaining fiber, the distributed fiber stress sensor with stress measuring range 0 to 15 MPa, spatial resolution 10 cm and measuring range 0.5 km, is designed. The warning system is also investigated experimentally in the field trial. 展开更多
关键词 distributed fiber optic stress sensor landslides warning monitoring system.
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Temperature and Salinity Dual-parameter Sensing Based on Forward Brillouin Scattering in 1060-XP SMF
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作者 LIU Pengkai ZHANG Wujun LU Yuangang 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2024年第S01期89-95,共7页
A novel temperature and salinity discriminative sensing method based on forward Brillouin scattering(FBS)in 1060-XP single-mode fiber(SMF)is proposed.The measured frequency shifts corresponding to different radial aco... A novel temperature and salinity discriminative sensing method based on forward Brillouin scattering(FBS)in 1060-XP single-mode fiber(SMF)is proposed.The measured frequency shifts corresponding to different radial acoustic modes in 1060-XP SMF show different sensitivities to temperature and salinity.Based on the new phenomenon that different radial acoustic modes have different frequency shift-temperature and frequency shift-salinity coefficients,we propose a novel method for simultaneously measuring temperature and salinity by measuring the frequency shift changes of two FBS scattering peaks.In a proof-of-concept experiment,the temperature and salinity measurement errors are 0.12℃and 0.29%,respectively.The proposed method for simultaneously measuring temperature and salinity has the potential applications such as ocean surveying,food manufacturing and pharmaceutical engineering. 展开更多
关键词 forward Brillouin scattering(FBS) optical fiber sensor salinity sensing temperature sensing
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