ELECTRO-MECHANICAL IMPEDANCE ( EMI)-BASED INCIPIENT CRACK MONITORING AND CRITICAL CRACK IDENTIFICATION OF BEAM STRUCTURES
ELECTRO-MECHANICAL IMPEDANCE ( EMI)-BASED INCIPIENT CRACK MONITORING AND CRITICAL CRACK IDENTIFICATION OF BEAM STRUCTURES
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DOI：
10.1080/09349847.2013.848311
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发表时间：
2014-04-03
影响因子：
1.4
通讯作者：
Soh, Chee Kiong
中科院分区：
文献类型：
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作者：
Lim, Yee Yan;Soh, Chee Kiong
疲劳引起的损伤通常是渐进和渐进的。老化结构的腐蚀往往会加剧疲劳，造成维护问题，甚至导致灾难性的故障。这就带动了结构健康监测（SHM）和无损检测（NDE）系统的发展。近年来，适用于SHM的智能材料的出现减轻了传统技术的缺点。使用智能压电换能器，自动、实时、远程监控成为可能。例如，机电阻抗（EMI）技术，采用压电换能器作为并行执行器和传感器，以其损伤检测和表征能力而闻名。本文介绍了一系列实验室规模的实验测试和分析，以研究利用电磁干扰技术检测和表征疲劳裂纹的可行性。本研究扩展了Lim和Soh[1]的工作，纳入了涉及裂纹起裂和临界裂纹的阶段。这表明电磁干扰技术是有效的表征疲劳诱发裂纹，即使在其初期阶段。该技术可以检测肉眼不可见的微裂纹，特别是在100-200kHz的较高频率范围内。提出了一种快速简便的基于定性的临界裂纹识别方法，即目视检测导纳频谱。
Fatigue-induced damage is often progressive and gradual in nature. Fatigue is often deteriorated by corrosion in ageing structures, creating maintenance problems, and even causing catastrophic failure. This ushers the development of structural health monitoring (SHM) and nondestructive evaluation (NDE) systems. Recent advent of smart materials applicable in SHM alleviates the shortcomings of the conventional techniques. Autonomous, real-time, remote monitoring becomes possible with the use of smart piezoelectric transducers. For instance, the electro-mechanical impedance (EMI) technique, employing piezoelectric transducers as collocated actuators and sensors, is known for its ability in damage detection and characterization. This article presents a series of lab-scale experimental tests and analysis to investigate the feasibility of fatigue crack detection and characterization employing the EMI technique. This study extends the work by Lim and Soh [1] to incorporate the phases involving crack initiation and critical crack. It is suggested that the EMI technique is effective in characterizing fatigue induced cracking, even in its incipient stage. Micro-crack invisible to the naked eyes can be detected by the technique especially when employing the higher frequency range of 100-200kHz. A quick and handy qualitative-based critical crack identification method is also suggested by visually inspecting the admittance frequency spectrum.