This paper presents the feasibility of using an impedance-based health moni
toring technique in monitoring a critical civil facility. The objective of
this research is to utilize the capability of the impedance method in ident
ifying structural damage in those areas where a very quick condition monito
ring is urgently needed, such as in a post-earthquake analysis of a pipelin
e system. The basic principle behind this technique is to utilize high-freq
uency structural excitation (typically greater than 30 kHz) through surface
-bonded piezoelectric sensors/actuators to detect changes in structural poi
nt impedance due to the presence of damage. Real-time damage detection in p
ipes connected by bolted joints was investigated, and the capability of the
impedance method in tracking and monitoring the integrity of the typical c
ivil facility has been demonstrated. Data collected from the tests illustra
tes the capability of this technology to detect imminent damage under norma
l operating conditions and immediately after a natural disaster. Copyright
(C) 2001 John Wiley & Sons, Ltd.