Multi-scale Smart Sensing of Vibration and Impedance for Structural Health Monitoring of Cable-stayed Bridge

Abstract

In this study, a multi-scale smart sensor system is developed for vibration and impedance-based structural health monitoring (SHM) of pylon-cable-deck system in cable-stayed bridge. The following approaches are implemented to achieve the objective. Firstly, theories of multi-scale responses of acceleration, PZT’s dynamic strain and electro-mechanical (E/M) impedance are described. Secondly, multi-scale vibration and impedance responses of pylon-cable-deck system in cable-stayed bridge are examined. Thirdly, vibration and impedance-based SHM methods suitable for the pylon-cable-deck system are examined. Fourthly, multi-scale smart sensor system is designed for the vibration and impedance-based SHM. The feasibility of the multi-scale smart sensor system is evaluated on a lab-scale cable-girder model. Finally, the practicality of the multi-scale smart sensor system is evaluated on a real cable-stayed bridge, Hwamyung Bridge in Korea. The system’s performance is experimentally analyzed under various cable forces and weather conditions. The experimental modal parameters are identified by numerical modal analyses of the target bridge. Also, its structural parameters are estimated from the modal strain energy-based system identification using experimental modal parameters.