Design of a d 33-mode piezocomposite electricity generating element and its application to bridge monitoring

Abstract

The piezoelectric effect is used in sensing applications such as in force and displacement sensors. However, the brittleness and low performance of piezoceramic lead zirconate titanate (PZT) often impede its applicability in civil structures which are subjected to large loads. The concept of a piezocomposite electricity generating element (PCGE) has been proposed for improving the electricity generation performance and overcoming the brittleness of piezoceramic wafers. The post-curing residual stress in the PZT layer constitutes a main reason for the PCGE’s enhanced performance, and the outer epoxy-based composites protect the brittle PZT layer. A d33-mode PCGE designed for bridge monitoring application was inserted in a bridge bearing to provide a permanent and simple weigh-in-motion system. The designed PCGEs were tested through a series of tests including fatigue and dynamic tests to verify their applicability for monitoring purposes in a bridge structure. A simple beam example was presented to show the applicability of the proposed bridge bearing equipped with the PCGE for adequately measuring the traffic loads.