Electromechanical Impedance Sensitivity Analysis Based Structural Health Monitoring using Sub-frequency for Compensating Temperature Effects

Abstract

Environmental temperature changes significantly affect the piezoelectric impedance spectrum signal, which may lead to damage misjudgment and damage omission if effective compensation measures are not taken. This article carries on the impedance spectrum signal of temperature sensitivity analysis, which shows a significant difference in the sensitivity with temperature of different frequency ranges. The cross-correlation coefficient is taken to quantitatively describe the impedance spectrum signal drift. The method of sub-frequency compensation is used to correct the impedance spectrum signal drift. The bolt looseness damage identification experiment under the influence of temperature using piezoelectric impedance method is carried out, and the result shows the effectiveness of sub-frequency compensation.