A new flexible FBG sensing beam for measuring dynamic lateral displacements of soil in a shaking table test

Dong Sheng Xu, Jianhua Yin, Zhen Zhong Cao, Yun Long Wang, Hong Hu Zhu, Hua Fu Pei

Research output: Journal article publicationJournal articleAcademic researchpeer-review

38 Citations (Scopus)

Abstract

In this paper, the design, validation, and application of a new flexible fiber Bragg grating (FBG) sensing beam are presented for effectively measuring dynamic lateral displacements inside soil mass in a shaking table test. The special flexible FBG sensing beam has been fabricated by employing a series of FBG sensors along with design of temperature compensation. Based on this design, equations of converting strains to lateral displacements are derived by using both differential and integral methods. Subsequently, the effectiveness of the FBG sensing beam has been verified in a shaking table test with non-contact laser displacement sensors (LDSs). The dynamic lateral displacements at different depths of the soil mass in the shaking table box throughout time history are calculated by differential and integral methods and compared with the results of LDSs. The comparison validates the measurement accuracy of the FBG sensing beam. Additionally, the Fast Fourier Transform (FFT) analysis result demonstrates that frequency measured by the sensing beam fits well with the results of traditional accelerometers and LDSs. Therefore, it can be concluded that the flexible FBG sensing beam is compatible with the stiffness of the soil and is capable of measuring dynamic lateral displacements with good accuracy in a shaking table test.
Original languageEnglish
Pages (from-to)200-209
Number of pages10
JournalMeasurement: Journal of the International Measurement Confederation
Volume46
Issue number1
DOIs
Publication statusPublished - 1 Jan 2013

Keywords

  • Dynamic lateral displacement
  • Fiber Bragg grating (FBG)
  • Fiber optic sensor
  • Shaking table test

ASJC Scopus subject areas

  • Instrumentation
  • Electrical and Electronic Engineering

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