Control of Civil Structures Using a Semiactive Stiffness System Based on Variable Amplification

Walsh, Kenneth K.; Abdullah, Makola M.; Moore, Carl A.

doi:10.1061/(asce)0733-9445(2008)134:7(1246)

Cited by 3 publications

(3 citation statements)

References 18 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Several damping devices have been proposed, studied and applied for applications to semi‐active and hybrid control. Among these are controllable fluid 9–12, variable friction 13–15 and variable orifice 16–19 dampers. Magnetorheological (MR) dampers, a type of controllable fluid dampers, have received considerable attention over the last decades because of their significant low power requirement, large resistance force, and fail‐safe nature, but their applications to civil structures is still in its infancy 20.…”

Section: Introductionmentioning

confidence: 99%

Modified friction device for control of large-scale systems

Laflamme

Taylor²,

Maane

et al. 2011

Struct. Control Health Monit.

View full text Add to dashboard Cite

SUMMARY Semi‐active control of civil structures has shown to be promising at mitigating vibrations. Those systems typically perform significantly better than passive systems, and only necessitate small power to operate. Nevertheless, semi‐active control devices are not yet accepted by the construction and structural engineering communities. Among impeding factors, semi‐active devices are not perceived as sufficiently reliable or robust. In this paper, a new semi‐active damping device based on existing reliable technology is proposed. It is composed of a stiffness element, a viscous damper, and a braking mechanism in parallel. The device, termed the modified friction device (MFD), is essentially a variable friction damper based on vehicular braking technology, equipped with a fail‐safe mechanism. The MFD is investigated as a replacement to the actual viscous damping contained in an existing structure in Boston, MA, for mitigation of accelerations caused by wind excitations. Simulations have showed that the MFD of 200 kN is capable of wind mitigation when compared with the performance of a passive viscous strategy of much larger capacity. Also, an MFD of 1350 kN capacity can perform similarly by using only a third of the number of dampers currently contained in the existing structure. Finally, the proposed device shows to be promising at mitigating inter‐story displacements in the occurrence of an earthquake. Copyright © 2011 John Wiley & Sons, Ltd.

show abstract

Section: Introductionmentioning

confidence: 99%

Modified friction device for control of large-scale systems

Laflamme

Taylor²,

Maane

et al. 2011

Struct. Control Health Monit.

View full text Add to dashboard Cite

show abstract

“…Combining Equations (19), (20), (23), and (24) yields the angle θ(t) in terms of the frame displacement as…”

Section: Scissor-jack-damper Displacement Amplificationmentioning

confidence: 99%

“…More recently, the displacement amplification device was developed . A similar device was proposed for semi‐active control by using variable amplification . In each case, rack and pinion mechanisms are used to connect the system between the structure and the damper .…”

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.

Self Cite

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

Seismic test of least-input-energy control with ground velocity feedback for variable-stiffness isolation systems

Chu

Yeh

et al. 2012

Journal of Sound and Vibration

View full text Add to dashboard Cite

Control of Civil Structures Using a Semiactive Stiffness System Based on Variable Amplification

Cited by 3 publications

References 18 publications

Modified friction device for control of large-scale systems

Modified friction device for control of large-scale systems

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

Seismic test of least-input-energy control with ground velocity feedback for variable-stiffness isolation systems

Contact Info

Product

Resources

About