Real-time Hybrid Test on a Semi-actively Controlled Building Structure Equipped with Full-scale MR Dampers

Abstract

The real-time hybrid testing method (RT-HYTEM) is a structural testing technique in which the numerical integration of the equation of motion for a numerical substructure and the physical testing for an experimental substructure are performed simultaneously in real-time. This article presents the quantitative evaluation of the seismic performance of a building structure installed with a magnetorheological (MR) damper using RT-HYTEM. A building model is identified from the force-vibration testing results of a full-scale five-story building and is used as the numerical substructure, and an MR damper corresponding to an experimental substructure is physically tested using a universal testing machine (UTM). First, the force required to drive the displacement of the story, at which the MR damper is located, is measured from the load cell attached to the UTM. The measured force is then returned to a control computer to calculate the response of the numerical substructure. Finally, the experimental substructure is excited by the UTM with the calculated response of the numerical substructure. The RT-HYTEM implemented in this study is validated because the real-time hybrid testing results obtained by application of sinusoidal and earthquake excitations and the corresponding analytical results obtained using the Bouc-Wen model as the control force of the MR damper with respect to input currents are in good agreement. Also, the results from RT-HYTEM for the passive -on and -off control show that the structural responses did not decrease further by the excessive control force, but decreased due to the increase of the current applied to the MR damper. Also, two semi-active control algorithms (modulated homogeneous friction and the clipped-optimal control algorithms) are applied to the MR damper in order to optimally control the structural responses. To compare the RT-HYTEM and numerical results, Bouc-Wen model parameters are identified for each input current. The results of the comparison of experimental and numerical responses show that it is more practical to use RT-HYTEM in semi-active devices such as MR dampers. The test results show that a control algorithm can be experimentally applied to the MR damper using RT-HYTEM. This article provides a discussion on each algorithm with respect to the seismic performances.

Keywords

real-time hybrid testing method numerical substructure experimental substructure MR damper seismic performance Bouc-Wen model semi-active control modulated homogeneous friction the clipped-optimal control.

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References

Adeli, H. and Saleh, A. 1999. Control, Optimization, and Smart Structures: High-performance Bridges and Buildings of the Future, John Wiley & Sons, Inc., New York.

Bitaraf, M. , Barroso, L.R. and Hurlebaus, S. 2010. ‘‘Adaptive Control to Mitigate Damage Impact on Structural Response,’’ J. Intell. Mater. Syst. Stuct., 21:607-619.

Blakeborough, A. , Williams, M.S. , Darby, A.P. and Williams, D.M. 2001. ‘‘The Development of Real-time Substructure Testing,’’ Phil. Trans. Ser. A. Math. Phys. Eng. Sci., 359:1869-1892.

Christenson, R. , Lin, Y.Z. , Emmons, A. and Bass, B. 2008. ‘‘Largescale Experimental Verification of Semiactive Control through Real-time Hybrid Simulation,’’ J. Struct. Eng., 134:522-534.

Dennis Jr, J.E. and Schnabel, R.B. 1983. Numerical Methods for Unconstrained Optimization and Nonlinear Equations, Prentice-Hall, Englewood Cliffs, NJ.

Dyke, S.J. , Spencer Jr, B.F. , Sain, M.K. and Carlson, J.D. 1996. ‘‘Modeling and Control of Magnetorheological Dampers for Seismic Response Reduction,’’ Smart Mater. Struct., 5:565-575.

Inaudi, J.A. 1997. ‘‘Modulated Homogeneous Friction: A Semi-active Damping Strategy,’’ Earthquake Eng. Struct. Dynam. , 26:361-376.

Jansen, L.M. and Dyke, S.J. 2000. ‘‘Semi-Active Control strategies for MR Dampers : A Comparative Study,’’ ASCE J. Eng. Mech., 126:795-803.

Kim, H. and Adeli, H. 2004. ‘‘Hybrid Control of Smart Structures Using a Novel Wavelet-Based Algorithm,’’ Comp. Aided Civ. Infrastruct. Eng., 20:7-22.

10.

Kim, H. and Adeli, H. 2005. ‘‘Hybrid Control of Irregular Steel Highrise Building Structures Under Seismic Excitations,’’ Int. J. Numer. Meth. Eng., 63:1757-1774.

11.

Kim, Y. , Langari, R. and Hurlebaus, S. 2009. ‘‘Semiactive Nonlinear Control of a Building with a Magnetorheological Damper System,’’ Mech. Syst. Signal Process., 23:300-315.

12.

Lee, S.-K. , Park, E.C. , Min, K.-W. , Lee, S.-H. , Chung, L. and Park, J.-H. 2007a. ‘‘Real-time Hybrid Shaking Table Testing Method for the Performance Evaluation of a Tuned Liquid Damper Controlling Seismic Response of Building Structures,’’ J. Sound Vib., 302:596-612.

13.

Lee, S.-K. , Park, E.C. , Min, K.-W. and Park, J.-H. 2007b. ‘‘Real-time Substructuring Technique for the Shaking Table Test of Upper Substructures,’’ Eng. Struct., 29:2219-2232.

14.

Lee, H.-J. , Yang, G. , Jung, H.-J. , Spencer Jr, B.F. and Lee, I.-W. 2006. ‘‘Semi-active Neurocontrol of a Base-isolated Benchmark Structure,’’ Struct. Contr. Health Monit. , 13:682-692.

15.

Nakashima, M. , Kato, H. and Takaokas, E. 1992. ‘‘Development of Real-time Pseudo Dynamic Testing,’’ Earthquake Eng. Struct. Dynam., 21:79-92.

16.

Pan, P. , Nakashima, M. and Tomofuji, H. 2005. ‘‘Online Test Using Displacement-force Mixed Control,’’ Earthquake Eng. Struct. Dynam. , 34:869-888.

17.

Spencer Jr, B.F. , Dyke, S.J. , Sain, M.K. and Carlson, J.D. 1997. ‘‘Phenomenological Model for Manetorheological Dampers,’’ J. Eng. Mech., 123:230-238.

18.

The MathWorks, Inc. 1999. Optimization Toolbox User’s Guide, The MathWorks, Natick, MA, USA.

19.

The MathWorks, Inc. 2007a. Signal Processing Toolbox User’s Guide, The MathWorks, Natick, MA, USA.

20.

The MathWorks, Inc. 2007b. Simulink Reference, MATLAB® SIMULINK®, Natick, MA, USA.

21.

The MathWorks, Inc. 2007c. Real-Time Windows Target 3 User’s Guide, MATLAB®SIMULINK® , Natick, MA, USA.

22.

Wen, Y.K. 1976. ‘‘Method of Random Vibration of Hyteretic Systems,’’ J. Eng. Mech. Div., ASCE., 102:249-263.

23.

Yang, G. , Spencer Jr, B.F. , Jung, H.-J. and Carlson, J.D. 2004. ‘‘Dynamic Modeling of Large-Scale Magnetorheological Damper Systems for Civil Engineering Applications,’’ J. Eng. Mech., 130:1107-1114.