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Algorithm Design for Intelligent Active Variable Stiffness System

지능형 변환강성시스템 알고리즘 설계

  • Received : 2016.09.26
  • Accepted : 2016.12.07
  • Published : 2016.12.30

Abstract

Active Variable Stiffness(AVS) System, which has on-off elements whose connection state to the main structure can be modulated by control signal, is one of the methods for controlling dynamic responses induced by earthquake or wind loads. AVS system, however, an impulse is transmitted to the structure when the connection state of the on-off elements gets changed. In the previous research, a function composed of displacement and velocity was presented to solve this problem, but the frequent changes of the connection state were observed and it was difficult for the linkage of the on-off elements to be mechanically implemented since the locking signal was given even when the displacements of the main structure and the on-off elements were different. In this study, the effects of the sudden linkage and separation of the on-off element were investigated, and a control algorithm which lets on-off elements linked when the displacement is close to zero and separated when accumulated static energy of the on-off elements starts to decrease was proposed. Numerical analysis was carried out to verify the availability of the proposed algorithm and the results indicated that the control performance could be maintained as the level of the previous study and the number of the connection state change was greatly reduced. Furthermore, unnecessary response magnification did not occur and the mechanical implementation of the proposed algorithm is possible because the linkage of the on-off elements was conducted only when the displacement was close to zero.

Keywords

Acknowledgement

Supported by : 한국연구재단

References

  1. Jin, S., Park, P.H., & Zhu, W. (2007). Micro-plate Tectonics and Kinematics in Northeast Asia Inferred from a dense set of GPS Observations, Earth and Planetary Science Letters, 257(3-4), 486-496. https://doi.org/10.1016/j.epsl.2007.03.011
  2. Park, B.C., Seong, J.Y., & Chang, S.H. (2014). Building Disaster and Safety Management using Seismic Acceleration Measurements, Journal of the Architectural Institute of Korea, 58(10), 36-40.
  3. Urban Safety Office of Seoul (2014), '15 Seismic Retrofit Measures for Existing Public Facilities, Seoul Metropolitan Government, 5-12.
  4. Urban Safety Office of Seoul (2015), The Current State of the Seismic Design of the Seoul Administrative Districts, Seoul Metropolitan Government.
  5. Soong, T. T., & Spencer, B. F. (2000). Active, Semi-active and Hybrid Control of Structure, Bulletin of the New Zealand National Society for Earthquake Engineering, 33(3), 387-402.
  6. Kobori, T., Takahashi, M., Niwa, N., & Kurata, N. (1991). Research on Active Seismic Response Control System with Variable Structure Characteristics -Feedback Control with Variable Stiffness and Damping Mechanism, Journal struct. eng., Architectural Institute of Japan, 37B, 193-202.
  7. Kobori, T., Takahashi, M., Nasu, T., Niwa, N., & Ogasawara, K. (1993). Seismic Response Controlled Structure with Active Variable Stiffness System, Earthquake engineering & structural dynamics, 22(11), 925-941. https://doi.org/10.1002/eqe.4290221102
  8. Golafshani, A.A., Kabiri, R.E., & Tabespour, M.R. (2006). A new high performance semi-active bracing system", Engineering Structures, 28, 1972-1982. https://doi.org/10.1016/j.engstruct.2006.03.032
  9. A. Fateh, F. Hejazi, M.S. Jaafar, I.A. Karim, & A.B. Adnan (2016). Design of a variable stiffness bracing system: Mathematical modeling, fabrication, and dynamic analysis, Soil Dynamics and Earthquake Engineering, 80, 87-101. https://doi.org/10.1016/j.soildyn.2015.10.009
  10. Kurino, H., Kobori, T., Takahashi, M., Niwa, N., Kurata, N., Matsunaga, Y., & Mizuno, T. (1996). Development and modeling of variable damping unit for active variable damping system, In Proceedings of the Eleventh World Conference on Earthquake Engineering, Acapulco, Mexico.
  11. Liu, Y., Matsuhisa, H., Utsuno, H., & Park, J. G. (2005). Vibration isolation by a variable stiffness and damping system, JSME International Journal Series C, 48(2), 305-310. https://doi.org/10.1299/jsmec.48.305
  12. Ping T., Fulin Z., & Weiming Y. (2010). A semi-active variable stiffness and damping system for vibration control of civil engineering structures, 2004 ANCEER Annual Meeting.
  13. Lee, S.H. (1998). Vibration Control of the Building Structures using Active Variable Stiffness System, Masters Thesis, Seoul National University.
  14. Lee, S.H., Hwang, J.S., & Min, K.W. (2001). Control Algorithm of Active Variable Stiffness System Based on Phase Plane Division, Journal of the Architectural Institute of Korea, 17(1), 27-34.
  15. Lee, Y.H., Heo, M.W., Roh, J.E., & Lee, S. (2016). Intelligent Control System Design Based on Phase Plane Division, COSEIK Annual Conference.
  16. Spencer, B.F., & Nagarajaiah, S. (2003). State of the Art of Structural Control, Journal of Structural Engineering, 127(7), 845-856.