Structural health monitoring using piezoelectric materials

• Main Author: Wee, Kim Hwee.
• Other Authors: Yang Yaowen
• Format: Final Year Project
• Language: English
• Published: 2013
• Subjects: DRNTU::Engineering::Civil engineering::Structures and design
• Online Access: http://hdl.handle.net/10356/52868
• Institution: Nanyang Technological University

There is a rising need for a structural health monitoring (SHM) method for civil and building structures all around the world nowadays. Amongst the various types of sensors available in the market used to monitor structural health, the Piezoelectric (PZT) transducer has been constantly in use and considered one of the more promising sensors because of its various advantages such as being cost effective, remote monitoring, able to be installed in very inaccessible places and being a method of non-destructive evaluation. In this study, a small PZT transducer patch is surface bonded to an aluminum beam specimen in an attempt to monitor the changes in the structure when tensile loading is applied via the admittance signatures which are obtained from an impedance analyzer. The experimental results are then analyzed using different methods in order to detect consistent changes in the peak frequency values on conductance signatures as loading is increased. From the experimental results, it shows that the PZT transducers are indeed capable of detecting the changes in the stress state of the aluminum specimen. Numerical modeling of the specimen is also carried out using the finite element software, ANSYS, to carry out an analytical study on the modal analysis of the aluminum specimen. The results of the numerical modeling and modal analysis showed close agreement with the experimental results. From the results of this numerical modeling, it can be seen that the PZT transducers are only capable of detecting a specific mode shape behavior out of the many different ones exhibited at different values of natural frequencies.