Strain and temperature calibration of Brillouin Optical Time Domain Analysis (BOTDA) sensing system

11th International Conference on Geotechnical Engineering in Tropical Regions;1st International Conference on Highway and Transportation Engineering 2019

矿业工程;运输工程

Ismail, Awang^1^2 ; Binti Siat Sirat, Qurratu Aini^2 ; Kassim, Azman Bin^2 ; Mohamad, Hisham Bin^3

Universiti Malaysia Sarawak, Malaysia^1

Universiti Teknologi Malaysia, Malaysia^2

Universiti Tekonologi PETRONAS, Malaysia^3

关键词: Brillouin frequency shifts;    Brillouin optical time domain analysis;    Effective approaches;    Geotechnical structure;    Rainfall infiltration;    Temperature calibration;    Temperature coefficient;    Thermal characteristics;   

Others  :  https://iopscience.iop.org/article/10.1088/1757-899X/527/1/012028/pdf
DOI  :  10.1088/1757-899X/527/1/012028

来源: IOP

【 摘 要 】

Instrumentation plays an important role in monitoring the performance of the geotechnical structures especially slope as it can be an effective approach for many unstable or potentially unstable. In the recent study, BOTDA interrogator is used to monitor the strain development on a laboratory soil slope model in order to assess the failure mechanism of residual soil slope under rainfall infiltration and surcharge loading. By understanding the concept of BOTDA technology which based on the Brillouin frequency shift (Δv b ), it possible to monitor changes in soil movement. Thus, the aim of the paper is to evaluate the parameter configuration of the BOTDA interrogator by determining both strain and temperature coefficients associated with the signal differences. The methodology presented as for acquiring the coefficients by calibrating the signal difference in terms of strain and thermal characteristics only for 12 ribbon Fujikura optical fibre sensor. As a result, the coefficient over a Brillouin signal for Fujikura optical fibre is 20 μ and 1°C for strain and temperature respectively. Therefore, the raw data obtained by the interrogator which in Megahertz unit can be evaluated in term of strain and temperature with respect to the coefficients.