Nonlinear piezoelectric impedance modulation induced by a contact-type failure and its application in crack monitoring
Nonlinear piezoelectric impedance modulation induced by a contact-type failure and its application in crack monitoring
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DOI：
10.1088/0964-1726/20/2/025021
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发表时间：
2011-01
影响因子：
4.1
通讯作者：
A. Masuda;J. Aoki;T. Shinagawa;D. Iba;A. Sone
中科院分区：
文献类型：
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作者：
A. Masuda;J. Aoki;T. Shinagawa;D. Iba;A. Sone
在本文中，自感知，敏感和无基线的结构健康监测方法的发展，其目的是检测和表征接触型的局部结构故障，即故障发生的产生，增长和/或改变的不完善的固-固界面。提出的非线性压电阻抗调制（NPIM）方法是基于现有的两个损伤检测原理的想法;压电阻抗为基础的方法和非线性波调制光谱。它采用一个粘贴在结构表面的压电主动传感器，由一个高频谐波电压源驱动。当包括接触型故障的结构经受低频动态载荷时，由于接触声学非线性（CAN），所诱发的结构振动导致故障处的高频弹性波的散射条件的波动。这种声振相互作用的非线性效应在高频范围内产生驱动点阻抗的显著波动，这可能导致压电有源传感器的耦合机电阻抗（或导纳）的调制。因此，如果传感器由固定幅度的高频谐波电压源驱动，则耦合导纳的调制可以被观察为流过传感器的电流的幅度调制和相位调制。一个简化的建模研究导致的损伤评估指标，评估由CAN引起的刚度波动的强度的定义。使用裂纹梁试样进行实验，以显示如何NPIM可以观察到，并检查所提出的方法的性能。
In this paper, a self-sensing, sensitive and baseline-free structural health monitoring methodology is developed, which aims to detect and characterize local structural failures of contact type, i.e. failures which arise along with the generation, growth and/or changes of imperfect solid–solid interfaces. The nonlinear piezoelectric impedance modulation (NPIM) method presented is based on the ideas of two existing damage detection principles; a piezoelectric impedance-based methodology and a nonlinear wave modulation spectroscopy. It uses a single piezoelectric active sensor bonded on the structural surface, which is driven by a high-frequency harmonic voltage source. When the structure including a contact-type failure is subjected to a low-frequency dynamic load, the induced structural vibration causes a fluctuation of the scattering conditions for the high-frequency elastic waves at the failure because of the contact acoustic nonlinearity (CAN). This nonlinear effect of vibro-acoustic interaction yields a significant fluctuation in the driving-point impedance in the high-frequency range, which may lead to a modulation of the coupled electromechanical impedance (or admittance) of the piezoelectric active sensor. Therefore, if the sensor is driven by a fixed amplitude high-frequency harmonic voltage source, modulation of the coupled admittance can be observed as the amplitude modulation and phase modulation of the current flowing through the sensor. A simplified modeling study leads to the definition of a damage evaluation index that assesses the intensity of the stiffness fluctuation caused by the CAN. Experiments using cracked beam specimens are conducted to show how the NPIM can be observed and to examine the performance of the proposed method.