Optimal design of friction pendulum system properties for isolated structures considering different soil conditions

Advanced nonlinear analysis in light rail transit (LRT) structures has been undertaken to examine the influence of seismic isolation devices for reducing seismic demand. The study employed the use of two types of commercially available bearings, namely lead rubber bearing (LRB) and friction pendulum system (FPS). Six LRT structures, designed to be built in Surabaya, were modelled using computer-aided software SAP2000, where each of the three structures consisted of three types of LRB and FPS placed onto the pier cap to support the horizontal upper-structural member. Nonlinear static pushover and dynamic time history analysis with seven improved ground motion data was performed to gain improved insights on the behavioural response of LRT structures, allowing one to fully understand the supremacy of seismic isolations for protecting the structure against seismic actions. It is shown that both devices manage to isolate seismic forces, resulting in alleviation of excessive base shear occurring at the column. In addition, it is noticeable that the overall responses of LRB and FPS shows marginal discrepancies, suggesting both devices are interchangeable to be used for LRT-like structures.

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Finite element formulation and shaking table tests of direction-optimized-friction-pendulum system

Engineering Structures ◽

10.1016/j.engstruct.2007.12.023 ◽

2008 ◽

Vol 30 (9) ◽

pp. 2321-2329 ◽

Cited By ~ 16

Author(s):

C.S. Tsai ◽

Po-Ching Lu ◽

Wen-Shin Chen ◽

Tsu-Cheng Chiang ◽

Chen-Tsung Yang ◽

...

Keyword(s):

Finite Element ◽

Shaking Table ◽

Finite Element Formulation ◽

Element Formulation ◽

Shaking Table Tests ◽

Pendulum System ◽

Friction Pendulum ◽

Friction Pendulum System

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Experimental Study of Friction Pendulum System to Improve the Seismic Capacity of Transformer

Journal of the Earthquake Engineering Society of Korea ◽

10.5000/eesk.2008.12.2.001 ◽

2008 ◽

Vol 12 (2) ◽

pp. 1-8 ◽

Cited By ~ 3

Keyword(s):

Experimental Study ◽

Seismic Capacity ◽

Pendulum System ◽

Friction Pendulum ◽

Friction Pendulum System

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Seismic Mitigation Assessment of Building Using Multiple Direction Optimized-Friction Pendulum System

Volume 8: Seismic Engineering ◽

10.1115/pvp2008-61366 ◽

2008 ◽

Author(s):

C. S. Tsai ◽

Wen-Shin Chen ◽

Yung-Chang Lin ◽

Chi-Lu Lin

Keyword(s):

Finite Element ◽

Shaking Table Test ◽

Shaking Table ◽

Finite Element Formulation ◽

Element Formulation ◽

Natural Period ◽

Pendulum System ◽

Friction Pendulum ◽

Seismic Mitigation ◽

Friction Pendulum System

In order to prevent a building near a fault from earthquake damage, in this study an advanced base isolation system called the multiple direction optimized-friction pendulum system (Multiple DO-FPS or MDO-FPS) is proposed and examined to address its mechanical behavior through the finite element formulation and evaluate its efficiency in seismic mitigation through a series of shaking table tests. On the basis of the finite element formulation, it is revealed that the natural period, the capacity of the bearing displacement and damping effect for the Multiple Direction Optimized-Friction Pendulum System (Multiple DO-FPS) change continually during earthquakes. Therefore, the MDO-FPS isolator can avoid possibility of resonance of enriched frequencies from ground motions and provide an efficient capacity of the bearing displacement and damping during the earthquakes. Simultaneously, the shaking table test results also illustrate that the Multiple DO-FPS isolator possesses an outstanding seismic mitigation capabilities.

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Multiple Yield and Bounding Surfaces Model for Analysis of Multiple Friction Pendulum System

Volume 8: Seismic Engineering ◽

10.1115/pvp2009-77307 ◽

2009 ◽

Cited By ~ 1

Author(s):

C. S. Tsai ◽

Yung-Chang Lin ◽

H.-C. Su

Keyword(s):

Mechanical Characteristic ◽

Isolation System ◽

Pendulum System ◽

Damping Effect ◽

Proposed Model ◽

Sliding Interfaces ◽

In Series ◽

Friction Pendulum ◽

Bounding Surfaces ◽

Friction Pendulum System

In order to systematically investigate the mechanical characteristic of a multiple friction pendulum system with more than two concave sliding interfaces and one articulated slider located between these concave sliding interfaces, on the basis of the plasticity theory, a plasticity model called the multiple yield and bounding surfaces model is proposed in addition to analytical formulations derived from the proposed concept of subsystems in this study. The proposed model has two separate groups of multiple yield and bounding surfaces. The first group is adopted to describe the mechanical behavior of the subsystem including the concave sliding interfaces above the articulated slider and the second group is used for modeling the sliding characteristic of the subsystem representing the concave sliding interfaces below the articulated slider. The connection of these two subsystems in series forms the mechanical characteristic of the entire MFPS isolation system. By virtue of the proposed model, the phenomena of the sliding motions of the MFPS isolator with multiple concave sliding interfaces under cyclical loadings can be clearly understood. Analytical results infer that the natural frequency and damping effect of the MFPS isolator with multiple concave sliding interfaces change continually during earthquakes and are controllable through appropriate designs.

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