Experiments on a base-isolated building in Santiago, Chile
ruben boroschek1998, Engineering Structures
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Abstract
An experimental four-story building, supported on high damping rubber isolators, was constructed in Santiago, Chile in 1992. The building and a conventional twin, standing nearby, are instrumented with a local network of digital accelerometers. At least 24 earthquakes of different intensities have been registered in the past three years by the recording system. Data was also obtained at the isolated building for pull-back testing in an effort to evaluate the constitutive characteristics of the bearings. This paper describes the bearing verification testing program as well as the experiments carried out at the isolated building. It also contains the analysis of the records obtained for actual earthquakes, for both the isolated and the conventional building, using parametric and non-parametric identification techniques. For the earthquake records obtained, the reduction in the maximum acceleration at the roof level for the isolated building, as compared to the conventional one, varies from 1 to 3.5 times, depending on the level of the maximum ground acceleration and the characteristics of the earthquake motions.
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All rights reserved. No part of contents of this paper may be reproduced or transmitted in any form or by any means without the written permission of Faculty of Civil Engineering, Universiti Teknologi Malaysia
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