Assessment of the Structural Integrity of Timber Utility Poles Using Ultrasonic Waves

Assessment of the Structural Integrity of Timber Utility Poles Using Ultrasonic Waves

Jad El Najjar, Samir Mustapha

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Abstract. In this study, guided stress waves were used to evaluate the conditions of a timber utility pole experimentally and numerically using COMSOL Multiphysics. Macro Fiber Composites (MFCs), due to their flexibility and convenience to install on curved surfaces, were used to actuate and sense guided waves along the tested specimens. Based on the wave propagation characteristics in these types of structures, an MFC actuator ring, which was developed in the previous work, was applied to tune and enhance the propagating wave modes of interest. The designed ring was used to excite longitudinal ultrasonic wave modes, mainly L(0,1), for the purpose of determining the embedded length of the pole. For the damage localization a single MFC excitation was used which proved to be more efficient than the actuator ring. Embedding the timber in soil had minimum impact on the wave propagation characteristics, given that the waves were confined in the timber pole with minimal leakage to the surrounding. The embedded length was determined accurately for sound and damage timber, using both experimental and numerical data with an error of less than 3 %. The deterioration in the timber structure, within the embedded region, was also evaluated with high accuracy of 93 %. Based on the obtained results, guided waves have high potential to be used as a non-destructive tool for the assessment and evaluation of timber utility poles.

Structural Health Monitoring, Timber Utility Poles, Guided Waves, Macro Fiber Composites, Damage Detection, Embedded Length Assessment

Published online 2/20/2021, 15 pages
Copyright © 2021 by the author(s)
Published under license by Materials Research Forum LLC., Millersville PA, USA

Citation: Jad El Najjar, Samir Mustapha, Assessment of the Structural Integrity of Timber Utility Poles Using Ultrasonic Waves, Materials Research Proceedings, Vol. 18, pp 131-145, 2021


The article was published as article 16 of the book Structural Health Monitoring

Content from this work may be used under the terms of the Creative Commons Attribution 3.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.

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