Experimental application of a wireless earthquake damage monitoring system (WiAMS) using PZT transducers in reinforced concrete beams

Abstract

An innovative portable wireless real time structural health monitoring system that can detect the earthquake damage and the structural integrity of reinforced concrete members in seismic-prone regions is experimentally evaluated. Damage detection is achieved by the use of piezoelectric transducers (actuators/sensors) and the implementation of an integration analytical approach based on the electromechanical impedance method. In this direction, piezoelectric lead zirconate titanate (PZT) transducers are bonded on the surface of the steel reinforcing bars of two large-scale reinforced concrete beams. Tested beams subjected to typical flexural monotonic and cyclic loadings and damage monitoring was performed at different loading levels, before and after yielding, using the developed system. Comparisons of the response signals acquired from the bonded piezoelectric patches for the healthy and the damaged states showed a clear gradation of the examined damage levels and provide cogent evidence that the monitoring system is sensitive from an early stage of the performed tests. The effectiveness of this structural health Wireless impedance or Admittance Monitoring System (WiAMS) to detect concrete cracking and steel yielding due to seismic excitations is also commented on. First results showed that the use of PZTs for detecting earthquake damages in reinforced concrete structures by employing the electromechanical impedance approach can be considered as a highly promising non-destructive structural health monitoring method.