Optimum Properties of Seismic Isolation Systems in Highway Bridges to Minimize Isolator Displacements or Substructure Forces

Date

2019-07-06

Author

Dicleli, Murat

Metadata

Show full item record

Item Usage Stats

298
views

0
downloads

In this study, closed form equations as functions of the isolator, bridge and ground motion properties are formulated to calculate the optimum characteristic strength, Qd and post-elastic stiffness, kd, of the isolator to minimize the maximum isolator displacement (MID) and force (MIF) for seismic isolated bridges (SIBs). For this purpose, first, sensitivity analyses are conducted to identify the bridge, isolator and ground motion parameters that affect the optimum values of Qd and kd. Next, for the identified parameters, nonlinear time history analyses of typical SIBs are conducted to determine the optimum values of Qd and kd for a wide range of values of the parameters. Next, nonlinear regression analyses of the available data are conducted to obtain closed form equations for the optimum values of Qd and kd to minimize the MID and MIF. The equations are then simplified for various site soil conditions. It is observed that the optimum Qd and kd are highly dependent on the site soil condition. However, the effect of the bridge substructure stiffness on the optimum Qd and kd and the effect of the structural or supplemental damping on the optimum kd are found to be negligible. Furthermore, the optimum Qd is found to be a linear function of the peak ground acceleration.

Subject Keywords

Seismic isolation, Bridge, Optimization, Site soil

URI

https://hdl.handle.net/11511/79671
http://www.16wcsi.org/?q=node/162

Conference Name

16th World Conference on Seismic Isolation, Energy Dissipation and Active Vibration Control of Structures

Collections

Department of Engineering Sciences, Conference / Seminar

Suggestions

OpenMETU
Core

Optimal Isolator Parameters for Economical Mitigation of Seismic Risk for Highway Bridges Dicleli, Murat (null; 2009-06-28) In this study, closed form equations as functions of the isolator, bridge and ground motion properties are formulated to calculate the optimum characteristic strength, Qd and post-elastic stiffness, k d, of the isolator to minimize the maximum isolator displacement (MID) and force (MIF) for seismic isolated bridges (SIBs). This formulation required more than 13000 nonlinear time history analyses of simplified SIB models. The analyses results revealed that the optimum Qd and k d are highly dependent on the s...
Estimation of optimum isolator parameters for effective mitigation of seismic risk for bridges Karalar, M.; Dicleli, Murat (2010-07-15) In this study, closed form equations as functions of the isolator, bridge and ground motion properties are formulated to calculate the optimum characteristic strength, Q(d) and post-elastic stiffness, k(d), of the isolator to minimize the maximum isolator displacement (MID) and force (MIF) for seismic isolated bridges (SIBs). This formulation required more than 13000 nonlinear time history analyses of simplified SIB models. The analyses results revealed that the optimum Qd and kd are highly dependent on the...
Optimum characteristic properties of isolators with bilinear force-displacement hysteresis for seismic protection of bridges built on various site soils Dicleli, Murat (Elsevier BV, 2011-07-01) In this study, closed form equations as functions of the isolator, bridge and ground motion properties are formulated to calculate the optimum characteristic strength, Q(d) and post-elastic stiffness, k(d), of the isolator to minimize the maximum isolator displacement (MID) and force (MIF) for seismic isolated bridges (SIBS). For this purpose, first, sensitivity analyses are conducted to identify the bridge, isolator and ground motion parameters that affect the optimum values of Q(d) and k(d). Next, for the...
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...
Optimum design of rigid and semi-rigid steel sway frames including soil-structure interaction Doğan, Erkan; Saka, M. Polat; Department of Engineering Sciences (2010) In this study, weight optimization of two dimensional steel frames is carried out in which the flexibility of beam-to-column connections and the soil-structure interaction are considered. In the analysis and design of steel frames, beam-tocolumn connections are assumed to be either fully rigid or perfectly pinned. However, the real behavior of beam-to-column connections is actually between these extremes. Namely, even the simple connections used in practice possess some stiffness falling between these two c...

Citation Formats

M. Dicleli, “Optimum Properties of Seismic Isolation Systems in Highway Bridges to Minimize Isolator Displacements or Substructure Forces,” presented at the 16th World Conference on Seismic Isolation, Energy Dissipation and Active Vibration Control of Structures, St.Petersburg, Russian Federation, 2019, Accessed: 00, 2021. [Online]. Available: https://hdl.handle.net/11511/79671.