Structural Health Monitoring under Varying Environmental Conditions Using Wavelets

Abstract:

A novel structural health monitoring system to detect damages in structures under varying operational and environmental conditions is presented in this paper. A noncontact, full-field measurement using a high speed camera offers a convenient and less expensive measurement procedure, enabling the measuring of responses in elevated temperatures and in conditions where contact sensors are unable to be used. In this paper, a combination of Decay lines of the Wavelet Transform Modulus Maxima (WTMM) and Holder Exponent (HE) are used to distinguish changes on the time response of a vibrating structure due to the operational and environmental variations to changes due to the presence of damage, thus minimising the possibility of false alarm. The proposed methodology is demonstrated using a 3-DOF system under conditions of varying and constant temperatures with the presence of damage, as well as using an experimental setup of a cantilever beam under intact and damaged conditions.

• Periodical: Key Engineering Materials (Volumes 569-570)
• Pages: 1218-1225
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.569-570.1218
• Online since: July 2013
• Authors: Andreas Tjirkallis, Andreas Kyprianou, George Vessiaris
• Keywords: Digital Video Imaging, Holder Exponent, Structural Health Monitoring (SHM), WTMM

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