An Optical Interferometric Triaxial Displacement Sensor for Structural Health Monitoring: Characterization of Sliding and Debonding for a Delamination Process

Chen Zhu; Yizheng Chen; Yiyang Zhuang; Yang Du; Rex E Gerald; Yan Tang; Jie Huang

doi:10.3390/s17112696

An Optical Interferometric Triaxial Displacement Sensor for Structural Health Monitoring: Characterization of Sliding and Debonding for a Delamination Process

Sensors (Basel). 2017 Nov 22;17(11):2696. doi: 10.3390/s17112696.

Authors

Chen Zhu¹, Yizheng Chen², Yiyang Zhuang³, Yang Du⁴, Rex E Gerald⁵, Yan Tang⁶, Jie Huang⁷

Affiliations

¹ Department of Electrical and Computer Engineering, Missouri University of Science and Technology, Rolla, MO 65409, USA. cznwq@mst.edu.
² Department of Electrical and Computer Engineering, Missouri University of Science and Technology, Rolla, MO 65409, USA. ycb28@mst.edu.
³ Department of Electrical and Computer Engineering, Missouri University of Science and Technology, Rolla, MO 65409, USA. yz8r4@mst.edu.
⁴ Department of Electrical and Computer Engineering, Missouri University of Science and Technology, Rolla, MO 65409, USA. duya@mst.edu.
⁵ American Inventor Institute, Willow Spring, IL 60480, USA. rexgeraldii@gmail.com.
⁶ Department of Electrical and Computer Engineering, Missouri University of Science and Technology, Rolla, MO 65409, USA. yty93@mst.edu.
⁷ Department of Electrical and Computer Engineering, Missouri University of Science and Technology, Rolla, MO 65409, USA. jieh@mst.edu.

Abstract

This paper presents an extrinsic Fabry-Perot interferometer-based optical fiber sensor (EFPI) for measuring three-dimensional (3D) displacements, including interfacial sliding and debonding during delamination. The idea employs three spatially arranged EFPIs as the sensing elements. In our sensor, the three EFPIs are formed by three endfaces of three optical fibers and their corresponding inclined mirrors. Two coincident roof-like metallic structures are used to support the three fibers and the three mirrors, respectively. Our sensor was calibrated and then used to monitor interfacial sliding and debonding between a long square brick of mortar and its support structure (i.e., a steel base plate) during the drying/curing process. This robust and easy-to-manufacture triaxial EFPI-based 3D displacement sensor has great potential in structural health monitoring, the construction industry, oil well monitoring, and geotechnology.

Keywords: debonding; extrinsic Fabry–Perot interferometer; interfacial sliding; structural health monitoring; three-dimensional displacement.