Vertical and Lateral Behavior of Unbonded Fiber-Reinforced Elastomeric Isolators
Publication: Journal of Composites for Construction
Volume 21, Issue 5
Abstract
Fiber-reinforced elastomeric isolators (FREIs) are relatively lightweight, can be cut to the required size from larger pads, and can be placed unbonded (i.e., unfastened) between the supports. The two major geometric parameters that influence the vertical and lateral response of unbonded fiber-reinforced elastomeric isolators (U-FREIs) are the shape factor and the aspect ratio. The vertical response is strongly influenced by the shape factor, while the aspect ratio is the controlling parameter for the stable response of U-FREIs under lateral displacement. This paper describes an experimental study on the vertical and lateral response of U-FREIs under different loading conditions in both the lateral and vertical directions. Three U-FREIs, with different aspect ratios and shape factors, were tested using a multiload test apparatus. Results from vertical tests indicate that, in addition to the shape factor, the vertical stiffness is influenced by the vertical rate of loading. Furthermore, it was found that the static lateral offset did not significantly affect the vertical stiffness of the isolators considered. These observations are in part attributed to the composite action of the fiber reinforcement and the elastomer.
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Acknowledgments
Financial support for this study was provided by the McMaster University Centre for Effective Design of Structures (CEDS) funded through the Ontario Research and Development Challenge Fund (ORDCF) as well as an Early Researcher Award (ERA) grant, both of which are programs of the Ministry of Research and Innovation (MRI). The support of the Natural Sciences and Engineering Research Council of Canada and a Vanier Canada Graduate Scholarship is gratefully acknowledged.
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Information & Authors
Information
Published In
Journal of Composites for Construction
Volume 21 • Issue 5 • October 2017
Copyright
©2017 American Society of Civil Engineers.
History
Received: Jul 20, 2016
Accepted: Nov 1, 2016
Published ahead of print: Feb 24, 2017
Published online: Feb 25, 2017
Discussion open until: Jul 25, 2017
Published in print: Oct 1, 2017
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