Seismic Response Case Study of Isolated Floor System Having Special Biaxial Spring Units
Publication: Journal of Structural Engineering
Volume 142, Issue 12
Abstract
This paper presents the results of a shake-table case study conducted on a proposed novel type of isolated floor system having special bidirectional spring units. This solution provides enhanced seismic performance for certain facilities where constraints may require isolation of select floors or spaces rather than the entire structure (typically for selected rooms in critical facilities). This system was tested on a 6-DOF shake table. The floor seismic excitations were obtained from nonlinear time history analyses of both single-degree-of-freedom and multidegree-of-freedom frames stiffened with buckling restrained braces and designed as a structural fuse frame, and subjected to synthetic ground motions. The test results show that the isolated floor system performs satisfactorily, but that system behavior differs from that of the spring units alone because correction must be made to account for sources of friction beyond those from the spring units alone. The mechanical properties of the isolated floor system are also obtained in terms of the acceleration–displacement relationship, which provides the foundation to better simulate these isolated floor systems in future parametric studies.
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Acknowledgments
This work was supported in whole by the Earthquake Engineering Research Centers Program of the National Science Foundation under Award No. ECC-9701471 to the Multidisciplinary Center for Earthquake Engineering Research. However, any opinions, findings, conclusions, and recommendations presented in this paper are those of the writers and do not necessarily reflect the views of the sponsors.
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Published In
Journal of Structural Engineering
Volume 142 • Issue 12 • December 2016
Copyright
© 2016 American Society of Civil Engineers.
History
Received: Mar 6, 2015
Accepted: May 1, 2016
Published online: Jul 11, 2016
Published in print: Dec 1, 2016
Discussion open until: Dec 11, 2016
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