Seismic Modeling of Skewed Bridges with Elastomeric Bearings and Side Retainers
Publication: Journal of Bridge Engineering
Volume 10, Issue 4
Abstract
Elastomeric expansion bearings are often restrained laterally by retainers on each side. The retainers are in the form of a concrete shear block, rolled steel angles, or welded plates. To allow for longitudinal temperature movements, the retainers are placed with a slight clearance (gap) from the elastomer. The gap introduces nonlinearity in the seismic analysis of the bridge and, therefore, is often ignored by designers for the sake of simplicity. This paper compares the seismic response of straight and skewed slab-girder single-span bridges under the conditions of zero gap and standard gap for the retainers. Nonlinear time-history analysis is employed to measure the seismic demand on retainers, elastomers, and pinned bearings in each case. The stiffness of end-diaphragms and elastomeric bearings is included in the analysis. It is shown that these relationships are nonlinear in nature and depend on the frequency content of the input motion. It is also proved that ignoring the nonlinearity in the seismic bridge model can lead to erroneous results that are unsafe to use.
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References
American Association of State Highway and Transportation Officials (AASHTO). (1998). LRFD bridge design specification, Washington, D.C.
Illinois Department of Transportation (IDOT). (1999). Bridge manual, Springfield, Ill.
Maleki, S. (2000). “Effect of elastomeric bearings on seismic response of skewed bridges.” Proc., 5th Int. Conf. on Computational Structures Technology, Civil-Comp Press, Stirling, U.K., 177–82.
Maleki, S. (2001a). “Effects of diaphragms on seismic response of skewed bridges.” Proc., 1st MIT Conf. on Computational Solid and Fluid Mechanics, Elsevier, Oxford, U.K., 681–84.
Maleki, S. (2001b). “Free vibration of skewed bridges.” J. Vib. Control, 8(8), 935–952.
Maleki, S. (2002a). “Effect of deck and support stiffness on seismic response of slab-girder bridges.” Eng. Struct., 24(2), 219–226.
Maleki, S. (2002b). “Deck modeling for seismic analysis of skewed slab-girder bridges.” Eng. Struct., 24(10), 1315–1326.
Maleki, S. (2004). “Effect of side retainers on seismic response of bridges with elastomeric bearings.” J. Bridge Eng., 9(1), 95–100.
SAP2000, version 7.4: Integrated structural analysis and design software. (2000). Computers and Structures, Berkeley, Calif.
Zahrai, S. M., and Bruneau, M. (1998). “Impact of diaphragms on seismic response of straight slab-on-girder bridges.” J. Struct. Eng., 124(8), 938–947.
Information & Authors
Information
Published In
Journal of Bridge Engineering
Volume 10 • Issue 4 • July 2005
Pages: 442 - 449
Copyright
© 2005 ASCE.
History
Received: Jul 8, 2003
Accepted: Jul 13, 2004
Published online: Jul 1, 2005
Published in print: Jul 2005
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