Piezoelectric Patch Sensors for Structural Integrity Monitoring of Composite-Upgraded Masonry and Concrete Structures

摘要

An acoustical impedance-based structural integrity monitoring technique employing piezoelectric (PE) patch sensor/actuators was used to detect real-time damage introduced to composite-upgraded wall test specimens. Concrete and brick masonry wall sections externally upgraded with fiber-reinforced polymer (FRP) composite materials were subjected to various stresses in a load test machine. During the tests, the wall sections were periodically interrogated via the PE sensor/actuators and electrical impedance measurements were made at various frequencies. When damage was present, the impedance vs frequency signature changed. Furthermore, there was a marked difference between the signature pattern for loading and for debonding of the composite upgrade or cracking of the concrete/masonry substrate. This report includes details on the development of the impedance-based technique and documents a demonstration of the technology on a composite-upgraded pier at Norfolk, VA.