Damage Detection for Curved Surfaces Using Advanced Piezo Impedance Transducers

Abstract

In recent years, it is necessary to monitor every civil and mechanical structure for the safety of human life and property. By using PZT, monitoring of structures is possible with some limitations such as direct attachment to the host structure, structure subjected to impact from external forces, inaccessible structure, high temperature locations, and structures with complex geometry and curved surfaces. To overcome these limitations, a new technique is employed for structural health monitoring. Using the advanced technique, transducer is prepared by attaching PZT with metal connectors which is in turn attached to the monitored structure. This paper demonstrates experimental study on mild steel pipes. Different aspects of SHM are studied. The proposed technique effectively detects locations of damages and severity of damages of pipe specimen. The technique is also employed to study effect of temperature variation along with detecting progressive damage of pipe specimen when it is subjected to steady constant high temperature. This technique is applicable to high temperature locations as the temperature of PZT maintained below its Curie temperature by introducing metal connector between structure and PZT patch. For the quantification of damages, the RMSD index formula is used.