Resilience-based performance and design of SMA/sliding bearing isolation system for highway bridges

A study is made of the seismic behaviour of base-isolated highway bridges with the objective of developing design procedures in the form of code-type approach. The recommendations of current codes concerning the use of energy dissipation mechanisms for the seismic design of bridges are reviewed. A model representing the bridge deck, piers, and the base-isolation system is used to evaluate the response of the bridge to a selected earthquake time history record and to evaluate the effects of various design parameters on the dynamic response. The results of this analysis are used in the development of design guidelines for the isolated bridge system. It was found that base isolation affects the design forces on piers and abutments as well as the deck displacements. An optimum design should provide a reasonable balance between the shear forces on supports and tolerable displacements. Two design procedures are proposed based on the time history and inelastic response spectra approaches. Simplified charts are presented which aid in the seismic design of new bridges as well as in the upgrading of existing ones. Key words: dynamic, seismic, design, highway, bridges, earthquake, base isolation.

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Dynamic Characteristics of a Sliding Bearing Using Lubricant Material for Base Isolation of Light Structures

Seismic Engineering ◽

10.1115/pvp2003-2101 ◽

2003 ◽

Author(s):

Nobuo Masaki ◽

Sadamitsu Takeuchi ◽

Hisashi Hirata

Keyword(s):

Coefficient Of Friction ◽

Base Isolation ◽

Damping Factor ◽

Sliding Bearings ◽

Sliding Bearing ◽

Isolation System ◽

Wooden House ◽

The Coefficient Of Friction ◽

Base Isolation System ◽

Rubber Bearings

The authors have been developed a system for base isolation of a wooden house and a prefabricate house. It consists of sliding bearings and laminated rubber bearings. There are two types of sliding bearings, one has the coefficient of friction of 0.046, the other has 0.06. Each of sliding bearings supports 30 ∼ 40kN of vertical load, the surface pressure of the sliding shoe is 10 ∼ 12 N/mm2 (10∼12MPa). The horizontal stiffness of the laminated rubber bearing is 38.5N/mm. For base isolation of an ordinary wooden house, 12 ∼ 16 sliding bearings and 4 ∼ 6 laminated rubber bearings are used. If the mass of a wooden house is 40ton and it is supported by 16 sliding bearings of the coefficient of friction of 0.046 and attached by 4 laminated rubber bearings with the horizontal stiffness of 38.5 N/mm, therefore it has 0.249 of the equivalent damping factor and 3.2 second of the natural period. As for the base isolated houses which are used this system, 500 houses have been constructed in Japan currently by the August of 2002 (Takahashi, 2002). As an advanced system of this base isolation system, we have developed a new type of the base isolation system of sliding bearing using silicone lubrication materials and rubber spring devices.

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Study of Sliding Bearing and Helical‐Steel‐Spring Isolation System

Journal of Structural Engineering ◽

10.1061/(asce)0733-9445(1991)117:4(1257) ◽

1991 ◽

Vol 117 (4) ◽

pp. 1257-1275 ◽

Cited By ~ 35

Author(s):

M. C. Constantinou ◽

A. S. Mokha ◽

A. M. Reinhorn

Keyword(s):

Sliding Bearing ◽

Isolation System ◽

Steel Spring

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Connection of a Scanning Tunneling Microscope with a Molecular Beam Epitaxy Chamber and Analysis of the Vibration Isolation System

Journal de Physique III ◽

10.1051/jp3:1995231 ◽

1995 ◽

Vol 5 (11) ◽

pp. 1871-1885 ◽

Cited By ~ 3

Author(s):

P. Krapf ◽

J.P. Lainé(*) ◽

Y. Robach ◽

L. Porte

Keyword(s):

Molecular Beam Epitaxy ◽

Scanning Tunneling Microscope ◽

Molecular Beam ◽

Vibration Isolation ◽

Scanning Tunneling ◽

Isolation System ◽

Vibration Isolation System ◽

Tunneling Microscope ◽

Molecular Beam Epitaxy Chamber

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An hourglass-type electromagnetic isolator with negative resistance electromagnetic shunt circuit

International Journal of Applied Electromagnetics and Mechanics ◽

10.3233/jae-209363 ◽

2020 ◽

Vol 64 (1-4) ◽

pp. 549-556

Author(s):

Yajun Luo ◽

Linwei Ji ◽

Yahong Zhang ◽

Minglong Xu ◽

Xinong Zhang

Keyword(s):

Vibration Isolation ◽

Electromechanical Coupling ◽

Coupling Effect ◽

Negative Resistance ◽

Isolation System ◽

Amplitude Vibration ◽

Vibration Responses ◽

The Stability ◽

Isolation Performance ◽

Shunt Circuit

The present work proposed an hourglass-type electromagnetic isolator with negative resistance (NR) shunt circuit to achieve the effective suppression of the micro-amplitude vibration response in various advanced instruments and equipment. By innovatively design of combining the displacement amplifier and the NR electromagnetic shunt circuit, the current new type of vibration isolator not only can effectively solve the problem of micro-amplitude vibration control, but also has significant electromechanical coupling effect, to obtain excellent vibration isolation performance. The design of the isolator and motion relationship is presented firstly. The electromechanical coupling dynamic model of the isolator is also given. Moreover, the optimal design of the NR electromagnetic shunt circuit and the stability analysis of the vibration isolation system are carried out. Finally, the simulation results about the transfer function and vibration responses demonstrated that the isolator has a significant isolation performance.

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