Please use this identifier to cite or link to this item: https://hdl.handle.net/10356/96002
Title: Comparative study of electromechanical impedance and lamb wave techniques for fatigue crack detection and monitoring in metallic structures
Authors: Lim, Say Ian
Liu, Yu
Soh, Chee Kiong
Keywords: DRNTU::Engineering::Materials::Metallic materials
Issue Date: 2012
Source: Lim, S. I., Liu, Y., & Soh, C. K. (2012). Comparative Study of Electromechanical Impedance and Lamb Wave Techniques for Fatigue Crack Detection and Monitoring in Metallic Structures. Proceedings of SPIE-Sensors and Smart Structures Technologies for Civil, Mechanical, and Aerospace Systems 2012, 8345.
Abstract: Fatigue cracks often initiate at the weld toes of welded steel connections. Usually, these cracks cannot be identified by the naked eyes. Existing identification methods like dye-penetration test and alternating current potential drop (ACPD) may be useful for detecting fatigue cracks at the weld toes. To apply these non-destructive evaluation (NDE) techniques, the potential sites have to be accessible during inspection. Therefore, there is a need to explore other detection and monitoring techniques for fatigue cracks especially when their locations are inaccessible or cost of access is uneconomical. Electro-mechanical Impedance (EMI) and Lamb wave techniques are two fast growing techniques in the Structural Health Monitoring (SHM) community. These techniques use piezoelectric ceramics (PZT) for actuation and sensing. Since the monitoring site is only needed to be accessed once for the instrumentation of the transducers, remote monitoring is made possible. The permanent locations of these transducers also translate to having consistent measurement for monitoring. The main focus of this study is to conduct a comparative investigation on the effectiveness and efficiency of the EMI technique and the Lamb wave technique for successful fatigue crack identification and monitoring of welded steel connections using piezoelectric transducers. A laboratory-sized non-load carrying fillet weld specimen is used in this study. The specimen is subjected to cyclic tensile load and data for both techniques are acquired at stipulated intervals. It can be concluded that the EMI technique is sensitive to the crack initiation phase while the Lamb wave technique correlates well with the crack propagation phase.
URI: https://hdl.handle.net/10356/96002
http://hdl.handle.net/10220/10064
DOI: http://dx.doi.org/10.1117/12.915064
Rights: © 2012 Society of Photo-Optical Instrumentation Engineers (SPIE). This paper was published in Proceedings of SPIE-Sensors and Smart Structures Technologies for Civil, Mechanical, and Aerospace Systems 2012 and is made available as an electronic reprint (preprint) with permission of Society of Photo-Optical Instrumentation Engineers (SPIE). The paper can be found at the following official DOI: [http://dx.doi.org/10.1117/12.915064].  One print or electronic copy may be made for personal use only. Systematic or multiple reproduction, distribution to multiple locations via electronic or other means, duplication of any material in this paper for a fee or for commercial purposes, or modification of the content of the paper is prohibited and is subject to penalties under law.
Fulltext Permission: open
Fulltext Availability: With Fulltext
Appears in Collections:CEE Conference Papers

Files in This Item:
File Description SizeFormat 
20. Comparative study of electromechanical impedance and Lamb wave techniques.pdf1.13 MBAdobe PDFThumbnail
View/Open

Google ScholarTM

Check

Altmetric

Items in DR-NTU are protected by copyright, with all rights reserved, unless otherwise indicated.