Seismic Capacity Evaluation of Exterior Shear Keys of Highway Bridges
Publication: Journal of Bridge Engineering
Volume 22, Issue 2
Abstract
Shear keys as sacrificial components are widely used in cap beams and abutments of highway bridges to limit the transverse displacement of superstructures and avoid damage of substructures. To investigate the seismic capacity of bridge exterior shear keys, six exterior shear key specimens were designed on the basis of current Chinese seismic design guidelines of highway bridges and subsequently tested under monotonic lateral loading. The influence of vertical and horizontal reinforcement ratios on the seismic capacity of the bridge shear keys was studied. Two typical failure modes of the exterior shear key specimens, diagonal tension failure and sliding shear failure, were observed during the tests. The reinforcement ratios of the shear key and cap beam have significant influence on the seismic capacity of exterior shear keys. Moreover, different analytical models corresponding to the two failure modes were developed to predict the seismic capacity of the shear key specimens in this paper. Compared with the experimental results, the two analytical models proposed in this study can better predict the load-carrying capacity of the shear key specimens than the classical analytical models.
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Acknowledgments
This research is jointly funded by the National Natural Science Foundation of China (NSFC) (Grants 51421005 and 51578022) and the National Program on Key Basic Research Project (Grant 2011CB013600). This support is gratefully acknowledged. The results and conclusions presented in the paper are those of the authors and do not necessarily reflect the view of the sponsors.
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Information
Published In
Journal of Bridge Engineering
Volume 22 • Issue 2 • February 2017
Copyright
© 2016 American Society of Civil Engineers.
History
Received: Dec 14, 2015
Accepted: Jun 22, 2016
Published online: Oct 14, 2016
Published in print: Feb 1, 2017
Discussion open until: Mar 14, 2017
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