The objective of this chapter is to examine and obtain a better understanding of practical issues that are a result of monitoring the health of structures in an uncontrolled field environment. The effects of external boundary and environmental condition changes and other structural variations on the impedance-based health monitoring technique are investigated. Examples of the factors that consi...

Components used for thermal protection have not previously been interrogated with the impedance method. In this study, structures are fabricated to represent typical thermal protections systems. The replicas are designed to simulate actual protection systems in use. Observations are made into the verification of the impedance method in effectively monitoring complex thermal protection systems f...

The objective of this chapter is to report the feasibility of using the impedance-based health monitoring technique for structures in an extremely high-temperature environment. The needs for on-line health monitoring system for these structures, such as steam pipes and boilers in power plants, are in great demand to avoid catastrophic failures. Currently, power plants rely on numerical methods ...

This research reviews and extends the impedance-based structural health monitoring technique in order to detect and identify structural damage on various complex structures. The basic principle behind this technique is to apply high frequency structural excitations (typically higher than 30 kHz) through the surface-bonded piezoelectric transducers, and measure the impedance of structures by mon...

The research presented in this manuscript introduces an independent structural health monitoring (SHM) system capable of performing impedance-based testing and detecting shifts in resonant frequencies. This independent structural health monitoring system incorporates a low power wireless transmitter that sends a warning signal when damage is detected in a structure. Two damage detection techniq...

The electro-mechanical (E/M) impedance method has gained acceptance as an effective technique for structural health monitoring, damage detection, and failure prevention. In spite of extensive experimental validation of this novel method, very little work has been dedicated to its modeling. This paper develops a model of the E/M impedance response of a damaged composite beam interrogated by a PZ...

The electro-mechanical (E/M) impedance method for structural health monitoring, damage detection and failure prevention is a new technology utilizing the emitter-detector properties of active material sensors and the structural drive point mechanical impedance. In previous work, the authors showed that changes in the drive point mechanical impedance of a structure or machinery can be sensed in ...

Electrical Impedance Tomography (EIT) as an imaging technique producing a 2D or 3D impedance image (conductivity or impedivity) of the subject under test. It can be used for delamination detection and evaluating the damage location, size, strain and severity for Structure Health Monitoring (SHM) of aerospace composites i.e. Carbon-fibrereinforced polymer (CFRP) composites. Keywords—Electrical I...