The 14th World Conference on Earthquake Engineering

The ability to monitor the health of an instrumented structure, detect damage as it occurs, and issue an early warning during or soon after the earthquake (or some other natural or man made disaster), and before physical inspection is possible, has significant potential benefits in reducing loss of life and injuries, in emergency response, and in recovery following the disaster. The timeliness of such information, even when the damage is obvious or there is no structural damage, is very useful to a building owner, of an important business or a critical facility. To be practically useful, the structural health monitoring systems must be robust when applied to real data, reliable, and sufficiently sensitive and accurate. This paper reviews briefly the current methods, trends and outstanding issues in practical implementation of such systems, with emphasis on a new method based on detecting changes in wave travel times using impulse response functions. This method can be viewed as an intermediate scale method, bridging the gap between the NDT and global vibrational methods. Results are shown as proof of concept studies using data from full scale buildings.