A Passive Rotary System for Seismic Risk Mitigation of Steel Structures
This paper presents a novel bracing system designed for earthquake risk mitigation for steel structures. It involves a rotary system which a Chebyshev linkage connected to the ground and the building frame. Upon earthquake excitation, movement of structure floor slabs causes a rotational motion in the disc. Displacement-based dampers are installed between the rotary system and the ground which damp the structural vibrations. The system amplifies the travel of the dampers and efficiency is enhanced. In addition, the cross-brace members are always in tension, permitting the use of very slender sections. The paper first reviews the governing equations of the system, followed by a physical model demonstration. A 3-degree-of-system model with the proposed rotary system was subjected to simulated ground shaking. Acceleration on top floor was measured. Results demonstrated that proposed system effectively supresses the vibrational characteristics of the structure, and represents a viable and inexpensive solution to mitigate seismic risks.
Keywords: Earthquake engineering, passive energy dissipation
Black, C., Makris, N. & Aiken, I. 2004. Component Testing, Seismic Evaluation and Characterization of Buckling-Restrained Braces. Journal of Structural Engineering, 130(6), 880-894.
Chan, R. & Albermani, F. 2013. Buckling-restrained-lug connection for energy dissipation. Advances in Structural Engineering, 16(1), 11-20.
Chan, R. W. K. & Albermani, F. 2008. Experimental study of steel slit damper for passive energy dissipation. Engineering Structures, 30 (4), 1058-1066.
Chan, R. W. K., Albermani, F. & Williams, M. S. 2009. Evaluation of yielding shear panel device for passive energy dissipation. Journal of Constructional Steel Research, 65(2009), 260-268.
Constantinou, M., Tsopelas, P., Hammel, W. & Sigaher, A. 2001. Toggle-Brace-Damper Seismic Energy Dissipation Systems. Journal of Structural Engineering, 127(2), 105-112.
Grigorian, C. E., Yang, T. S. & Popov, E. P. 1993. Slotted Bolted Connection Energy Dissipators. Earthquake Spectra, 9(3), 491-504.
Kang, J. D. & Tagawa, H. 2013. Seismic response of steel structures with seesaw systems using viscoelastic dampers. Earthquake Engineering and Structural Dynamics, 42(5), 779-794.
SIgaher, A. N. & Constantinou, M. C. 2003. Scissor-Jack-Damper Energy Dissipation System. Earthquake Spectra, 19(1), 133-158.
Symans, M., Charney, F., Whittaker, A., Constantinou, M., Kircher, C., Johnson, M. & Mcnamara, R. 2008. Energy Dissipation Systems for Seismic Applications: Current Practice and Recent Developments. Journal of Structural Engineering, 134(1), 3-21.
Tagawa, H. & Gao, J. 2012. Evaluation of vibration control system with U-dampers based on quasi-linear motion mechanism. Journal of Constructional Steel Research, 70(2012), 213-225.
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