Seismic Design and Performance of Ductile End-Diaphragms in Slab-on-Girder Steel Bridges with Flexible Substructure
Publication: Journal of Bridge Engineering
Volume 22, Issue 11
Abstract
Conventionally, in the conceptual seismic design of bridges, absorption of earthquake energy is provided through plastic deformation in the main components of the bridge, such as columns and walls. In recent decades, ductile end-diaphragms have been proposed as one of the passive control systems to reduce the inelastic deformation in the substructure of steel bridges by transferring the majority of seismic energy dissipation to diaphragm inelastic deformations under ground motion in the transverse direction. The proper operation of these systems with stiff substructures has been already demonstrated in several numerical and experimental studies, but the need for separate studies about their design and performance in steel bridges with flexible substructures is quite tangible. In this article, first, the generalized single-degree-of-freedom (SDOF) dimensionless relations of single-span and continuous three-span bridges located on flexible piers are developed. Then, using some assumptions, the relations are extended to the inelastic range. Different forms of ductility imposed on bridges equipped with ductile end-diaphragms, including global, support, diaphragm, and damper ductility, are identified. Moreover, using simplified analyses, a new step-by-step design method is proposed, and the accuracy of the results is verified using nonlinear time-history analyses for some numerical examples. The simultaneous role of the substructure stiffness and deck flexural stiffness and the contribution of girder stiffness in the design and evaluation of ductile diaphragms are examined. Results indicate that increasing flexibility of the substructure may result in superstructure damage like yielding of the girders or impractical required damper components. Although the main focus of this article is on the design of ductile end-diaphragms, because of the subject generality, the concepts can be extended to slab-on-girder steel bridges equipped with other yielding devices.
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References
AASHTO. (2009). LRFD bridge design specification. Washington, DC.
Alfawakhiri, F., and Bruneau, M. (2001). “ Local versus global ductility demands in simple bridges.” J. Struct. Eng., 554–560.
Astaneh-Asl, A., Bolt, B., McMullin, K. M., Donikian, R. R., Modjtahedi, D., and Cho, S. W. (1994). “ Seismic performance of steel bridges during the 1994 Northridge earthquake.” Rep. UCB/CESTEEL-94/01, Dept. of Civil Engineering, Univ. of California, Berkeley, CA.
Bahrami, H., Itani, A. M., and Buckle, I. G. (2010). “ Guidelines for the seismic design of ductile end cross frames in steel girder bridge superstructures.” Rep. UNR/CCEER-09/04, Dept. of Civil and Environmental Engineering, Univ. of Nevada, Reno, NV.
Carden, L. P., Buckle, I. G., and Itani, A. M. (2007). “ Transverse displacement capacity and stiffness of steel plate girder bridge superstructures for seismic loads.” J. Constr. Steel Res., 63(11), 1546–1559.
Carden, L. P., Garcia-Alverez, F., Itani, A. M., and Buckle, I. G. (2006a). “ Cyclic behavior of single angles for ductile end cross frames.” Eng. J., 43, 111–126.
Carden, L. P., Itani, A. M., and Buckle, I. G. (2006b). “ Seismic performance of steel girder bridges with ductile cross frames using single angle X braces.” J Struct. Eng., 329–337.
Carden, L. P., Itani, A. M., and Buckle, I. G. (2006c). “ Seismic performance of steel girder bridges with ductile cross frames using buckling-restrained braces.” J Struct. Eng., 338–345.
Celik, O. C., and Bruneau, M. (2009). “ Seismic behavior of bidirectional-resistant ductile end diaphragms with buckling restrained braces in straight steel bridges.” Eng. Struct., 31(2), 380–393.
Chopra, A. K. (2001). Dynamics of structures: Theory and applications to earthquake engineering, 2nd Ed., Prentice-Hall, Upper Saddle River, NJ.
Itani, A. M., and Rimal, P. P. (1996). “ Seismic analysis and design of modern steel highway connectors.” Earthquake Spectra, 12(2), 275–296.
Ramirez, O. M., Constantinou, M. C., Whittaker, A. S., Kircher, C. A., and Chrysostomou, C. Z. (2002). “ Elastic and inelastic seismic response of buildings with damping systems.” Earthquake Spectra, 18(3), 531–547.
SAP2000 [Computer software]. Computers & Structures, Inc., Walnut Creek, CA.
Tsai, K.-C., Chen, H.-W., Hong, C.-P., and Su, Y.-F. (1993). “ Design of steel triangular plate energy absorbers for seismic-resistant construction.” Earthquake Spectra, 9(3), 505–528.
Zahrai, S. M., and Bruneau, M. (1998). “ Impact of diaphragms on seismic response of straight slab-on-girder steel bridges.” J. Struct. Eng., 938–947.
Zahrai, S. M., and Bruneau, M. (1999a). “ Ductile end-diaphragms for seismic retrofit of slab-on-girder steel bridges.” J. Struct. Eng., 71–80.
Zahrai, S. M., and Bruneau, M. (1999b). “ Cyclic testing of ductile end-diaphragms for slab on-girder steel bridges.” J. Struct. Eng., 987–996.
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Published In
Journal of Bridge Engineering
Volume 22 • Issue 11 • November 2017
Copyright
© 2017 American Society of Civil Engineers.
History
Received: Oct 5, 2016
Accepted: May 22, 2017
Published online: Sep 7, 2017
Published in print: Nov 1, 2017
Discussion open until: Feb 7, 2018
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