Performance improvement of seismic-isolated bridges near active faults using elastic-gap devices

Date

2017-04-27

Author

Dicleli, Murat

Metadata

Show full item record

Item Usage Stats

175
views

0
downloads

For seismic isolated bridges (SIBs) subjected to near-fault (NF) ground motions with directivity effect, the isolator displacements tend to be considerably large. Consequently, isolators with very large dimensions may be required for SIBs located in NF zones. This may lead to very large expansion joints and very large seat widths as well. In this research, the efficiency of providing supplemental elastic-gap devices to improve the performance of seismic-isolated bridges (SIBs) in near-fault (NF) zones is investigated. The device is primarily made of elastomeric bearings placed in parallel with seismic isolators to provide additional elastic stiffness upon closure of a gap. A parametric study, involving more than 400 nonlinear time history (nonlinear time-history) analyses of realistic and simplified structural models of typical SIBs are conducted using simulated and actual NF ground motions to investigate the applicability of the proposed solution. It is found that providing elastic-gap device is beneficial in reducing the isolator displacements to manageable ranges. It is also found that the gap and the stiffness of the elastic-gap device may be chosen in relation to the magnitude of the NF ground motion to minimize the isolator displacements by moving away from the high-energy region of the spectrum. Further analyses conducted using a realistic structural model of an existing bridge and five NF earthquakes with moderate to large magnitudes confirmed that elasticgap device may be used to reduce the displacement of the isolators while keeping the substructure base shear forces at practically acceptable ranges for SIBs located in NF zones.

URI

https://hdl.handle.net/11511/71967
http://db.nzsee.org.nz/2017/O4C.7_Dicleli.pdf

Conference Name

NZSEE Annual Technical Conference and 15th World Conference on Seismic Isolation, Energy Dissipation and Active Vibration Control of Structures (27 Nisan 2017)

Collections

Department of Engineering Sciences, Conference / Seminar

Suggestions

OpenMETU
Core

Elastic-gap device to enhance the performance of seismic-isolated bridges in near fault zones Dicleli, Murat (2018-09-28) For seismic isolated bridges (SIBs) subjected to near-fault (NF) ground motions with directivity effect, the isolator displacements tend to be considerably large. Consequently, isolators with very large dimensions may be required for SIBs located in NF zones. This may lead to very large expansion joints and very large seat widths as well. In this research, the efficiency of providing supplemental elastic-gap devices to improve the performance of seismic-isolated bridges (SIBs) in near-fault (NF) zones is in...
SEISMIC PERFORMANCE OF SINGLE-SPAN SIMPLY SUPPORTED AND CONTINUOUS SLAB-ON-GIRDER STEEL HIGHWAY BRIDGES Dicleli, Murat (1995-10-01) Seismic response of single-span simply supported and continuous slab-on-girder steel bridges is studied. Linear elastic and nonlinear inelastic analyses are conducted for various ground-acceleration inputs. Bearings with higher stiffnesses that are closer to the edge of the deck are found to attract larger forces than other bearings, whereas bearings with small stiffness attract almost equal forces regardless of the width of the brid e. Assuming that the anchors of otherwise stable bearings are severed, sli...
Equivalent linear analysis of seismic-isolated bridges subjected to near-fault ground motions with forward rupture directivity effect Dicleli, Murat (2007-01-01) This study encompasses the assessment of the equivalent linear (EL) analysis procedure for the design of seismic isolated bridges (SIB) subjected to near-fault ground motions with forward rupture directivity effect. The assessment procedure involves the comparison of the seismic response quantities obtained from EL analyses with those obtained from nonlinear time history (NLTH) analyses. The effect of several isolator and near-fault ground motion properties are considered in the assessment of the EL analysi...
Experimental evaluation of geomembrane / geotextile interface as base isolating system Taheri Bonab, Amin; Gülerce, Zeynep; Kalpakcı, Volkan; Department of Civil Engineering (2016) The objective of this study is to evaluate the effect of the composite liner seismic isolation system on the seismic response of small-to-moderate height structures. For this purpose, a building model with the natural frequency of 3.13 Hz (representing 3-4 story structures) was tested with and without the addition of composite liner system using the shaking table test set-up by employing harmonic and modified/ scaled ground motions. Experiment results showed that the composite liner seismic isolation system...
Seismic behavior of vertical reinforced autoclaved aerated concrete (AAC) panel walls Taghipour, Armin; Canbay, Erdem; Binici, Barış; Department of Civil Engineering (2016) In this study, the in-plane seismic behavior of autoclaved aerated concrete (AAC) vertical load-bearing wall panels is examined. Because of the complex behavior of AAC shear walls under cyclic lateral loading and axial load, the design provisions are fundamentally important. The main objective of this study is to validate proposed design provisions for AAC structures in Turkey. Six specimens with different properties and geometries were constructed and tested at Structural Mechanics Laboratory of METU. Mech...

Citation Formats

M. Dicleli, “Performance improvement of seismic-isolated bridges near active faults using elastic-gap devices,” Wellington, Yeni Zelanda, 2017, Accessed: 00, 2021. [Online]. Available: https://hdl.handle.net/11511/71967.