Affiliations: Department of Materials Engineering, The University of Tokyo, Tokyo, Japan
Note: [] Address for correspondence: T. Shiraiwa, Department of Materials Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan. E-mail: [email protected].
Abstract: A new sensor called “smart stress-memory patch” which can measure the stress amplitude and the number of fatigue cycles and the maximum stress related to a structure subjected to fatigue loading for efficient structural health monitoring has been proposed. However, there are two problems in the real applications of smart patch. Firstly, when the sensor is adhered to the structure, the sensing property of smart patch may change because the restrained condition of the sensor would be intricately changed. Secondly, high-precision crack measurement of smart patch by optical microscope is too cumbersome in the real field. In this study, thin electrodeposited (ED) Cu specimen was prepared and attached to steel bar as a sensor of smart patch. The fatigue test was performed to examine the fatigue crack growth of the sensor attached to the structure. Furthermore, wireless devices using low power wireless modules have been developed for efficient crack measurements, and wireless devices results give close agreement with the results by microscope.
Keywords: Fatigue crack growth, finite element method, sensor, structural health monitoring