Slope-assisted Raman distributed optical fiber sensing

Purpose Seepage of the dam is an important safety problem, which may cause internal erosion of the structure. In the field of seepage monitoring in civil engineering, the distributed optical fiber sensing technology based on the temperature tracing method has been paid more attention due to its unique advantages of high sensitivity, good stability and high resolution. The purpose of this paper is to make a review of the existing related research, so as to facilitate the later scholars to understand and further study more systematically. Design/methodology/approach In this paper, three kinds of commonly used distributed fiber temperature measurement technologies are introduced. Based on the working principle, monitoring system, theoretical analysis, experimental research and engineering application of the fiber seepage monitoring technology, the present situation of dam seepage monitoring based on distributed fiber is reviewed in detail and their advantages and disadvantages are compared. Findings The thermal monitoring technology of seepage measurement depends on the accuracy of optical fiber temperature measurement (including the accuracy of the system and the rationality of the discrimination method), the correct installation of optical fiber and the quantitative analysis of temperature data. The accuracy of the current monitoring system can basically meet the existing measurement requirements, but the correct installation of optical fiber and the calibration of temperature data need to be further studied for different discrimination methods, and this field has great research value. Originality/value At present, there are many applications and research studies of optical fiber sensing in the field of structural health monitoring, and there are also reviews of related aspects. However, there is little or no review only in the field of seepage monitoring. This paper summarizes the research and application of optical fiber sensing in the field of seepage monitoring. The possibility of the gradient method to find its new prospect with the development of monitoring systems and the improvement of temperature resolution is discussed. The idea of extending the seepage monitoring method based on distributed optical fiber thermal monitoring technology to other monitoring fields is also given in the paper.

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Distributed Optical Fiber Sensing Technology and Its Applications

Laser & Optoelectronics Progress ◽

10.3788/lop20094611.0029 ◽

2009 ◽

Vol 46 (11) ◽

pp. 29-33 ◽

Cited By ~ 1

Author(s):

刘德明 Liu Deming ◽

孙琪真 Sun Qizhen

Keyword(s):

Optical Fiber ◽

Fiber Sensing ◽

Sensing Technology ◽

Optical Fiber Sensing ◽

Distributed Optical Fiber

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Experimental Study on Deformation Monitoring of Bored Pile Based on BOTDR

Applied Sciences ◽

10.3390/app9122435 ◽

2019 ◽

Vol 9 (12) ◽

pp. 2435 ◽

Cited By ~ 6

Author(s):

Lei Gao ◽

Chuan Han ◽

Zhongquan Xu ◽

Yingjie Jin ◽

Jianqiang Yan

Keyword(s):

Optical Fiber ◽

Noise Removal ◽

Deformation Monitoring ◽

Optical Time Domain Reflectometer ◽

Fiber Sensing ◽

Bored Pile ◽

Sensing Technology ◽

Optical Fiber Sensing ◽

Unbiased Risk ◽

Distributed Optical Fiber

In order to study the deformation of bored pile, it is necessary to monitor the strain of the pile. The distributed optical fiber sensing technology realizes the integration of sensing and transmission, which is incomparable with traditional point monitoring method. In this paper, the Brillouin optical time domain reflectometer (BOTDR) distributed optical fiber sensing technology is used to monitor the deformation of the bored pile. The raw data monitored by BOTDR is processed by the wavelet basis function, that can perform noise removal processing. Three different methods of noise removal are chosen. Through the processing, the db5 wavelet is used to decompose the deformation data of bored pile monitored by BOTDR into two layers. The decomposed high-frequency signal is denoised by the Stein-based unbiased risk threshold, rigrsure. The decomposed data is smoothed by the translational mean method, and the final data after denoising and smoothing processing is real and reliable. The results of this study will provide data support for the deformation characteristics of bored pile, and also show the advantages of distributed optical fiber sensing technology.

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