Seismic response controlled structure with Active Variable Stiffness system

Kobori, Takuji; Takahashi, Motoichi; Nasu, Tadashi; Niwa, Naoki; Ogasawara, Katsura

doi:10.1002/eqe.4290221102

Cited by 266 publications

(143 citation statements)

References 2 publications

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“…By knowing the required damper flow rate , dynamic range , cylinder size , yield stress , plastic viscosity , and pressure drop , the gap size and active pole length can be obtained from Eqs. (32) and (33). However, this initial design needs to be verified by a more accurate axisymmetric model.…”

Section: Geometry Constraintsmentioning

confidence: 96%

Large-scale MR fluid dampers: modeling and dynamic performance considerations

Yang

Spencer

Carlson

et al. 2002

Engineering Structures

658

508

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The magnetorheological (MR) damper is one of the most promising new devices for structural vibration reduction. Because of its mechanical simplicity, high dynamic range, low power requirements, large force capacity and robustness, this device has been shown to mesh well with application demands and constraints to offer an attractive means of protecting civil infrastructure systems against severe earthquake and wind loading. In this paper, an overview of the essential features and advantages of MR materials and devices is given. This is followed by the derivation of a quasi-static axisymmetric model of MR dampers, which is then compared with both a simple parallel-plate model and experimental results. While useful for device design, it is found that these models are not sufficient to describe the dynamic behavior of MR dampers. Dynamic response time is an important characteristic for determining the performance of MR dampers in practical civil engineering applications. This paper also discusses issues affecting the dynamic performance of MR dampers, and a mechanical model based on the Bouc-Wen hysteresis model is developed. Approaches and algorithms to optimize the dynamic response are investigated, and experimental verification is provided.

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Section: Geometry Constraintsmentioning

confidence: 96%

Large-scale MR fluid dampers: modeling and dynamic performance considerations

Yang

Spencer

Carlson

et al. 2002

Engineering Structures

658

508

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show abstract

“…In contrast, when the valve is open, the fluid flows freely and disengages the stiffness control devices. The system may be regarded as fail-safe in the sense that the interruption of power causes the semi-active stiffness devices to automatically engage, thus increasing the stiffness of the structure (Kamagata and Kobori 1994;Kobori et al 1993;Yang et al 1996). In past, many researchers have investigated the seismic response of symmetric structures using stiffness dampers.…”

Section: Model Of Damper and Control Lawsmentioning

confidence: 99%

“…In past, many researchers have investigated the seismic response of symmetric structures using stiffness dampers. The non-resonant-type control system called as active variable systems were proposed by Kamagata and Kobori (1994) and Kobori et al (1993). This system produces a non-stationary, non-resonant condition during earthquakes which is achieved by altering the building's stiffness based on the nature of the earthquake.…”

Section: Model Of Damper and Control Lawsmentioning

confidence: 99%

Seismic response of torsionally coupled building with passive and semi-active stiffness dampers

Mevada¹,

Jangid

2015

Int J Adv Struct Eng

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The seismic response of single-storey, oneway asymmetric building with passive and semi-active variable stiffness dampers is investigated. The governing equations of motion are derived based on the mathematical model of asymmetric building. The seismic response of the system is obtained by numerically solving the equations of motion using state-space method under different system parameters. The switching and resetting control laws are considered for the semi-active devices. The important parameters considered are eccentricity ratio of superstructure, uncoupled lateral time period and ratio of uncoupled torsional to lateral frequency. The effects of these parameters are investigated on peak lateral, torsional and edge displacements and accelerations as well as on damper control forces. The comparative performance is investigated for asymmetric building installed with passive stiffness and semi-active stiffness dampers. It is shown that the semi-active stiffness dampers reduce the earthquake-induced displacements and accelerations significantly as compared to passive stiffness dampers. Also, the effects of torsional coupling on effectiveness of passive dampers in reducing displacements and accelerations are found to be more significant to the variation of eccentricity as compared to semi-active stiffness dampers.

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“…Variable stiffness devices have also been proposed by Kobori et al [1993], Nagarajaiah and Mate [1998], and Gluck et al [2000]. Furthermore, numerous algorithms have been developed for selecting the appropriate damping coefficient [Yang et al 1987;Soong 1990;Sadeck and Mohraz 1998;Cundumi 2005;Cundumi and Suárez 2006b].…”

Section: Have Beenmentioning

confidence: 99%

A new variable damping semiactive device for seismic response reduction of civil structures

Cundumi

Suárez

2007

JOMMS

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A semiactive mechanism, called a VDSA (variable damping semiactive device), is proposed to reduce the seismic response of structures. It is composed of two fixed-orifice viscous fluid dampers installed in the form of a V whose top ends are attached to a floor and their lower ends to a collar that moves along a vertical rod. By varying the VDSA position one obtains an optimal instantaneous damping added to the structure. The position of the moving end is calculated with an algorithm based on a variation of the instantaneous optimal control theory which includes a generalized LQR (linear quadratic regulator) scheme. This modified algorithm, referred to as Qv, is based on the minimization of a performance index J quadratic in the state vector, the control force vector, and an absolute velocity vector. Two variants of the algorithm are used to present numerical simulations of the controlled seismic response of a single and a MDOF (multi-degree-of-freedom) structure.

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Seismic response controlled structure with Active Variable Stiffness system

Cited by 266 publications

References 2 publications

Large-scale MR fluid dampers: modeling and dynamic performance considerations

Large-scale MR fluid dampers: modeling and dynamic performance considerations

Seismic response of torsionally coupled building with passive and semi-active stiffness dampers

A new variable damping semiactive device for seismic response reduction of civil structures

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