A Hi h-precision extensometer system for ground displacement measurement using Fiber Bragg Grating
Document Type
Article
Publication Date
5-1-2022
Abstract
The design and performance of an innovative high-precision extensometer system, fabricated inexpensively using 3D printing technology, are discussed in this paper. In the development of the extensometer, an embedded Fiber Bragg Grating (FBG) strain sensor was 3D printed using a thermoplastic polyurethane (TPU) filament, which was used as the primary sensing element of the extensometer system, taking advantage of its excellent flexibility and high sensitivity to variations in localized strain. In the performance assessment carried out, the results obtained during the experimental test and validation have demonstrated that it could be used very effectively to measure strain variations, with an average wavelength responsivity of 0.0158 nm/cm (for displacement) and very high linearity (up to 99%). Furthermore, the protection integrated into the sensor systems design makes it well-suited for in-the-field applications, such as monitoring ground displacements which can lead to dangerous slippages of sloped earthworks. In addition, a field testing of the extensometer under simulated conditions has shown that a Fiber Bragg Grating (FBG)-based approach could be applied effectively to the measurement of strain, offering a wavelength responsivity of 0.0012 nm/mu epsilon (for strain-sensitive FBGs) under both dry and wet soil conditions. Moreover, taking advantage of the high (similar to 99%) linearity, the extensometer is a reliable instrument for use in different underground conditions, creating an easy-to-use ground movement monitoring system which then enables an excellent representation of the displacement profile of the earth to be made.
Keywords
Extensometer, Strain measurements, Fiber Bragg Grating-based technology, 3D-printing, Ground movements
Divisions
PHYSICS,photonics
Funders
University of Malaya through the Grant UM Innovate (Grant No: PPSI-2020-HICOE-02),Newton Fund Impact Scheme Grant through the Newton-Ungku Omar Fund Partnership (Grant No: IF022-2020),U.K. Department for Business, Energy and Industrial Strategy,Royal Academy of Engineering - UK,Malaysian Industry-Government Group for High Technology (MIGHT)
Publication Title
IEEE Sensors Journal
Volume
22
Issue
9
Publisher
Institute of Electrical and Electronics Engineers (IEEE)
Publisher Location
445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA