Semi‐active friction system with amplifying braces for control of MDOF structures

Gluck, J.; Ribakov, Yuri

doi:10.1002/tal.168

Cited by 9 publications

(9 citation statements)

References 8 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…where G feedb is the optimal feedback gain matrix, depending on damper distribution, defined by matrix B and performance index J, given in Eqn (2);d t ð Þ is the optimal estimation of the structure's state vec- Figure 1. Amplifier's scheme (following Gluck and Ribakov [25,27]). tor d(t), generated by Kalman filter algorithm using the floors' accelerations y m (t).…”

Section: Effective Damper Locationsmentioning

confidence: 99%

“…To implement this equation, semiactive MR dampers are used in the frame of this study. Connecting damping devices to amplifiers allows further energy saving [25].The properties of MR dampers, placed at each floor, are controlled in real time during the earthquake. The properties are updated, based on analyzing the response of the structure, so that the forces, developed in semiactive MR dampers, are as close as possible to those obtained according to Eqn (4).…”

mentioning

confidence: 99%

See 1 more Smart Citation

Using a limited set of MR dampers for improving structural seismic response

Ribakov

Agranovich

2014

Struct. Control Health Monit.

View full text Add to dashboard Cite

Summary Control is one of the methods used for reducing structural response to earthquakes. Optimal active control algorithms allow calculating the forces that should be applied by supplemental devices in order to yield desired structural behavior during an earthquake. However, active devices require large amounts of external power, which are not always available in the real time. Therefore, more economical semiactive devices, combining the best features of passive and active control systems, are used for protecting structures against earthquakes. This study is aimed at finding a simple and effective method for optimal control of structures using magnetorheological dampers. An algorithm for finding effective dampers' locations is used. Additionally, high‐efficiency amplifiers are used for connecting the dampers while decreasing the number of damping units. The location of dampers is found by simulating the structural response to a white noise ground motion. A number of equivalent damping units with amplifiers are obtained assuming equal energy dissipation at minimum amplifying ratio. The effectiveness and performance of the proposed method are further demonstrated by simulating the response of the structure to natural earthquake records. Copyright © 2014 John Wiley & Sons, Ltd.

show abstract

Section: Effective Damper Locationsmentioning

confidence: 99%

mentioning

confidence: 99%

Using a limited set of MR dampers for improving structural seismic response

Ribakov

Agranovich

2014

Struct. Control Health Monit.

View full text Add to dashboard Cite

show abstract

“…In devices from the second group, the influence of electric or magnetic field on properties of fluids or solids is employed to change the damping forces. The first group includes a variable stiffness system (Kobori et al , 1993), a semi‐active hydraulic damper (Kurata et al , 1999), semi‐active friction dampers (Ferri and Heck, 1992; Gluck and Ribakov, 2001) and others. The second group of semi‐active controlled device includes electrorheological (Makris et al , 1996) or magnetorheological (MR) devices (Spencer et al , 1997) and semi‐active variable friction (VF) dampers with piezoelectric actuators (Chen and Chen, 2000).…”

Section: Introductionmentioning

confidence: 99%

“…Gluck and Ribakov. (2001) used amplifying devices and instantaneous control theory for increasing the efficiency of a damping system with VF. In order to overcome time delay in the control system, a predictive algorithm combined with instantaneous control (Gluck et al , 2000a) or a method developed from predictive and modal control (Lu 2004) may be used.…”

Section: Introductionmentioning

confidence: 99%

Base‐isolated structures with selective controlled semi‐active friction dampers

Ribakov

2011

Structural Design Tall Build

Self Cite

View full text Add to dashboard Cite

This paper investigates effectiveness of selective control strategy in hybrid base isolation systems including isolators and semi‐active variable friction (VF) dampers. According the selective control strategy, VF dampers are activated just if the displacement at the isolators exceeds the threshold value. The slip‐force control is based on the values of floors' accelerations and velocities. By controlling the slip‐force magnitude in the VF dampers, effective energy dissipation can be achieved in a seismic event. Activation of dampers according to the selective control strategy allows high‐energy dissipation by minimum energy required for adjusting the slip‐force. Performance of a multi‐storey frame with a base isolation system and VF dampers under various earthquake records was obtained numerically using originally developed MATLAB routines. Seismic response of the analysed structure with the selective controlled system was compared with that when the VF dampers were active during the whole earthquake. It is shown that adjustment of the slip‐force in a selective manner allows additional reductions in peak displacements and accelerations of the structure. The results also demonstrate that this control strategy yields reduction of the base displacement without increasing the peak base shear forces. Copyright © 2009 John Wiley & Sons, Ltd.

show abstract

“…Later, a design procedure was proposed to determine appropriate arm sizes while considering the desired amplification factor and allowable deflection . Another amplification system is the amplifying brace . This system has been shown to work well with a number of different supplemental damping devices .…”

Section: Introductionmentioning

confidence: 99%

Dynamic analysis of seismically excited flexible truss tower with scissor-jack dampers

Walsh

Cronin

Rambo-Roddenberry

et al. 2011

Struct. Control Health Monit.

View full text Add to dashboard Cite

SUMMARY In the proposed work, numerical simulations are conducted to investigate scissor‐jack dampers for controlling vibrations in a seismically excited flexible truss tower. For the scissor‐jack damper, new equations are developed to model the amplification factor that account for large deformations of the damper assembly. The equations are validated using computer‐aided design and are used to investigate the influence of vertical deformations on scissor‐jack damper amplification. Then, seismic analysis is carried out for scissor‐jack dampers installed on a 3D flexible truss tower. To reduce the computational effort, a bi‐model method is employed to represent the 3D truss tower as a dynamically equivalent 2D model. To describe the interaction between the structure and scissor‐jack dampers, the displacement‐dependent amplification factors of the scissor‐jack devices and the corresponding damper forces are calculated at each time step. The response of the tower with scissor‐jack damper systems is simulated for a range of damping and four major earthquakes and time histories of the displacement and absolute acceleration at each level of the tower are obtained. Results indicate that the system is effective in reducing both the displacement and absolute acceleration response of the tower without exceeding damper stroke capacity in most cases, but that damping level and earthquake intensity are important factors in the consideration of scissor‐jack dampers for flexible structures subject to seismic loads. Copyright © 2011 John Wiley & Sons, Ltd.

show abstract

Semi‐active friction system with amplifying braces for control of MDOF structures

Cited by 9 publications

References 8 publications

Using a limited set of MR dampers for improving structural seismic response

Using a limited set of MR dampers for improving structural seismic response

Base‐isolated structures with selective controlled semi‐active friction dampers

Dynamic analysis of seismically excited flexible truss tower with scissor-jack dampers

Contact Info

Product

Resources

About