Packaged in-line Mach-Zehnder interferometer for highly sensitive curvature and flexural strain sensing

摘要

The paper presents an innovative packaging approach to allow highly sensitive in-line Mach-Zehnder interferometer (IMZI) sensor to be used for accurate measurement of curvature and flexural strain specifically in civil engineering. The sensor which consists of two tapers is protected within a polypropylene package to survive in harsh, in-the-field conditions. The package design employs cost effective materials without compromising the curvature and flexural strain sensitivity which are 85.2 dB m(-1) and 0.0148 dB/mu epsilon. The accuracy of measurement results is further verified by obtaining the flexural modulus for the steel which is in good agreement with theoretical value. (C) 2016 Elsevier B.V. All rights reserved.