Author(s)

NOBUHIRO SHIMOI, CARLOS CUADRA, HIDETO KANNO

Abstract

Recently, sensors that use piezoelectric materials are studied to detect impacts, number of impact occurrences, vibrations, etc. in structures. One of them uses a piezoelectric film attached to a thin steel plate that is installed on a steel column-beam joint to investigate its mechanical behaviour. Since the piezoelectric material reacts when sudden changes occur, the piezoelectric film is covered by a thin glass plate, and it is expected that when glass plate cracks due to an applied load stress, the film will react by emitting a voltage signal. In this way it might be possible to detect certain level of damage in a structural steel joint. Using this sensor system, static tests of steel beam-column joints were carried out and the applicability of the sensor was verified. However, the sensor reaction begins at high levels of deformation and the cracking of the glass does not occurs in the central part of the sensor plate as it was expected. Then is this research a structural analysis of the sensor steel plate is performed to analyse the stress distribution and the possible causes of glass failure at the ends of the sensor plate. The load test was found to produce a bending moment on the sensor plate and this moment has a great influence on the location of the glass crack. Also, for reverse loading, the steel plate is subject to compressive stresses and buckling failure must be considered.

Keywords

piezoelectric sensor, seismic damages, compression failure, steel structure failure