Monitoramento de integridade estrutural baseado na técnica da impedância eletromecânica incorporando compensação do efeito da variação da temperatura

Abstract

Structural Health monitoring is a useful tool for reducing maintenance costs and improving life and performance of engineering structures. Impedance-Based SHM utilizes the coupled electromechanical behavior of piezoelectric materials to detect adverse changes due to material and mechanical failures of structures. Environmental conditions such as temperature present a challenge in providing diagnostics capable of distinguishing between structural damage and temperature effects. An effective frequency shift method was developed to compensate impedance measurements for changes resulting from environmental temperature fluctuations. This dissertation investigates how the accuracy of this method can be improved in terms of temperature range and frequency band used in the monitoring process. In order to reduce temperature effects from impedance measurements, this dissertation investigates the possibility of using several baselines to perform a more accurate diagnostic for structural integrity even under temperature variation applications.