Ambient Vibration Surveys of a Steel Frame Building Damaged in the Northridge Earthquake
Abstract
More than 150 steel frame buildings experienced failure in their beam-column connections as a result of the Northridge earthquake. Because the connections were not visible, many of the failures remained undetected for months after the earthquake. In order to better detect structural damage, there has been much research in structural health monitoring, with the goal being detection, location, and assessment of structural damage by vibration monitoring. Ambient vibration surveys (AVS) can be used to efficiently, cheaply and unobtrusively identify the small-amplitude periods and modeshapes of the lower modes of vibration of a structure. By applying AVS before and after an earthquake, any changes in the modal parameters can be used in structural health monitoring schemes. Results are presented from AVS performed on an 11-story steel-frame building in which nearly 30% of the steel connections were damaged during the Northridge earthquake. The building was tested both in its damaged state and after the connections were repaired. Based on these results, conclusions are drawn about the strengths and weaknesses of using ambient vibration surveys for structural health monitoring
Additional Information
Financial support from the SAC Phase I Steel Project is gratefully acknowledged. The authors would also like to thank Raul Relies of Caltech for his assistance in the field testing and Farzad Naeim of John A. Martin & Associates for helping us gain access to the building.Additional details
- Eprint ID
- 34418
- Resolver ID
- CaltechAUTHORS:20120926-095936789
- SAC Phase I Steel Project
- Created
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2012-10-31Created from EPrint's datestamp field
- Updated
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2021-08-23Created from EPrint's last_modified field