Study Between Laminated Rubber Bearings and Friction Pendulum Bearing of Base Isolation System: A Review

In the present paper the dynamic nonlinear analysis for a 3D base isolated structure is illustrated. A base isolated reinforced concrete building is designed and verified according to the European seismic codes such that the superstructure remains almost completely elastic and the nonlinear elements are localized only in the base isolation system. Nonlinear hysteretic models have been adopted to reproduce the cyclic behavior of the isolators. Two different base isolation systems are considered and their performances are compared for evaluating the behaviour of a base isolated building, highly irregular in plan, in presence of a seismic excitation defined with recorded accelerograms which characterize the bi-directional ground motions. The isolation system has been realized with a combination in parallel of elastomeric bearings and sliding devices. In the first analyzed isolation system we have used the High Damping Rubber Bearings (HDRB) and in the second analyzed isolation system we have used the Lead Rubber Bearings (LRB). Finally a comparative analysis between the base isolated structure with hybrid base isolation systems and the conventional fixed base structure is detailed.

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Seismic Responses of a Building Isolated With Multiple Friction Pendulum System Subjected to Multi-Directional Excitations

ASME 2010 Pressure Vessels and Piping Conference: Volume 8 ◽

10.1115/pvp2010-25587 ◽

2010 ◽

Cited By ~ 1

Author(s):

C. S. Tsai ◽

Yung-Chang Lin ◽

H. C. Su

Keyword(s):

Base Isolation ◽

Numerical Analyses ◽

Good Tool ◽

Isolation System ◽

Pendulum System ◽

Sliding Interfaces ◽

Base Isolation System ◽

Structural Responses ◽

Friction Pendulum ◽

Friction Pendulum System

In order to prevent a building from earthquake damage, a base isolation system called the multiple friction pendulum system (MFPS) which has numerous concave sliding interfaces is proposed to isolate a building from its foundation. Mathematical formulations have been derived to simulate the characteristic of the MFPS isolation system subjected to multi-directional excitations. By virtue of the derived mathematical formulations, the phenomena of the sliding motions of the MFPS isolator with several concave sliding interfaces under multi-directional earthquakes can be clearly understood. Also, numerical analyses of a building isolated with the MFPS isolator with several sliding interfaces have been conducted in this study to evaluate the efficiency of the proposed system in seismic mitigation. It has been proved through numerical analyses that structural responses have been reduced significantly and that the proposed system is a good tool to insure the safety of structures during earthquakes.

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Analysis of Vibration Control due to Strong Earthquakes

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.163-167.4179 ◽

2010 ◽

Vol 163-167 ◽

pp. 4179-4184 ◽

Cited By ~ 1

Author(s):

He Len Wu

Keyword(s):

Control System ◽

Active Control ◽

Base Isolation ◽

Hybrid Control ◽

Ground Motions ◽

Isolation System ◽

System A ◽

Base Isolation System ◽

Active Control System ◽

Hybrid Control System

The paper proposes an aseismic hybrid control system to control the response of structures subjected to large ground motions caused by large magnitude earthquakes. The proposed hybrid control system consists of a base isolation system (laminated rubber bearings) connected to an active control system (a tuned mass damper and an actuator). The base isolation system is used to decouple the horizontal ground motions from the structure, whereas the active control system is used to protect the safety and integrity of the base isolation system. A 5-story benchmark building model is developed to study the effectiveness of the hybrid control system against different ground motions. It was found from the numerical results that rubber bearing system alone shows good performance and resists ground motion due to Hachinohe 1968, Kobe 1995, and Northridge 1994 earthquakes, but is somewhat unable to protect the model against El-Centro 1940 earthquake. After the installation of an active control system onto the rubber-isolated model, further improvements to earthquake resistance against these four earthquakes were observed, especially against the El-Centro earthquake. The merit of the hybrid control system lies in its capability to protect against different ground motions, with varying intensity and frequency content.

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Design of Shape Memory Alloy Damper for Base Isolated Structure

Volume 1B: 16th Biennial Conference on Mechanical Vibration and Noise ◽

10.1115/detc97/vib-3824 ◽

1997 ◽

Author(s):

Krzysztof Wilde ◽

Paolo Gardoni ◽

Yozo Fujino ◽

Stefano Besseghini

Keyword(s):

Shape Memory Alloy ◽

Shape Memory ◽

Base Isolation ◽

Hysteretic Behavior ◽

Isolation System ◽

Rubber Bearing ◽

Laminated Rubber Bearing ◽

Base Isolation System ◽

Rubber Bearings ◽

Smart Base Isolation

Abstract Base isolation provides a very effective passive method of protecting the structure from the hazards of earthquakes. The proposed isolation system combines the laminated rubber bearing with the device made of shape memory alloy (SMA). The smart base isolation uses hysteretic behavior of SMA to increase the structural damping of the structure and utilizes the different responses of the SMA at different levels of strain to control the displacements of the base isolation system at various excitation levels. The performance of the smart base isolation is compared with the performance of isolation by laminated rubber bearings to assess the benefits of additional SMA damper for isolation of three story building.

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Influence of the Strain Hardening of HDRBs in the Evaluation of the Seismic Response of a RC Base Isolated Structure

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.602-604.1546 ◽

2012 ◽

Vol 602-604 ◽

pp. 1546-1554

Author(s):

Donato Cancellara ◽

Fabio de Angelis ◽

Mario Pasquino

Keyword(s):

Strain Hardening ◽

Seismic Response ◽

Base Isolation ◽

Cyclic Behavior ◽

Hysteretic Model ◽

Isolation System ◽

Limit Value ◽

Hardening Effect ◽

Base Isolation System ◽

Rubber Bearings

In this paper we have analyzed the influence of the strain hardening behavior of High Damping Rubber Bearings (HDRBs) adopted for a base isolation system of a Reinforced Concrete (RC) isolated structure. For the modeling of the rubber isolators we have adopted an evolution of the Bouc-Wen’s hysteretic model taking into account the incremental hardening effect which appears when the shear strain of the HDRB exceeds the limit value around 100% usually adopted in design practice. The incremental hardening effect is sometimes neglected in the design but it is an important aspect because it ensures a seismic protection of the base isolated structure also in presence of exceptional seismic events for intensity or frequency content. In this paper we have highlighted the significant influence of this phenomenon in the seismic response of the isolated structure by reporting the cyclic behavior of a HDRB respectively neglecting and considering this aspect.

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DEVELOPMENT OF BASE-ISOLATION SYSTEM CONSISTING OF SLIDING AND RUBBER BEARINGS

AIJ Journal of Technology and Design ◽

10.3130/aijt.2.69_1 ◽

1996 ◽

Vol 2 (2) ◽

pp. 69-73 ◽

Cited By ~ 3

Author(s):

Seiji TOMISHIMA ◽

Shoji KATSUTA ◽

Masayoshi HISANO

Keyword(s):

Base Isolation ◽

Isolation System ◽

Base Isolation System ◽

Rubber Bearings

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Applications of Multiple Trench Friction Pendulum System to Seismic Mitigation of Structures

Volume 8: Seismic Engineering ◽

10.1115/pvp2008-61344 ◽

2008 ◽

Author(s):

C. S. Tsai ◽

Jeng-Wen Lin ◽

Yung-Chang Lin ◽

Chia-Chi Chen

Keyword(s):

Base Isolation ◽

Shaking Table ◽

Shaking Table Tests ◽

Natural Period ◽

Isolation System ◽

Pendulum System ◽

Base Isolation System ◽

Friction Pendulum ◽

Seismic Mitigation ◽

Friction Pendulum System

In order to promote seismic resistance capability of structures and simplify the manufacturing processes of an isolator, a new base isolation system called the multiple trench friction pendulum system (MTFPS) is proposed. The investigations for the proposed isolator have been carried out to address its mechanical characteristics and to assess its performance in seismic mitigation through a series of shaking table tests in this study. The MTFPS isolator can provide different natural periods, displacement capacities and damping effects in any two independent directions. The natural period and damping effect for a MTFPS isolator change continually during earthquakes. Results from the shaking table tests on a scaled three-story structure isolated with MTFPS isolators illustrate that the proposed MTFPS isolator can isolate most earthquake induced energy and provide good protection for structures from earthquake damage. In addition, the mathematical formulations for the MTFPS isolator have also been derived to examine its characteristics.

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