Stochastic optimal control of wind-excited tall buildings using semi-active MR-TLCDs

A new semi-active control device, magneto-rheological tuned liquid column damper (MR-TLCD), has been devised recently by the authors for mitigation of wind-induced vibration response of tall building structures. The developed device combines the benefits of magneto-rheological smart materials and tuned liquid column dampers. In this paper, real-time semi-active vibration control of tall building structures incorporating nonlinear MR-TLCDs under random wind excitation is studied by means of the statistical linearization method and the optimal linear quadratic (LQ) control strategy. The equations of motion of a tall building structure subjected to random wind loading and controlled by using MR-TLCDs at the top floor are first derived and represented in modal coordinate. After linearizing the uncontrollable part of MR-TLCD damping force and incorporating it with structural components, the classical linear quadratic (LQ) control strategy is applied to the linearized structural system to determine optimal control force of the MR-TLCDs. Clipping treatment is performed to ensure the commanded control force implementable by the MR-TLCDs. Wind-excited response of the semi-actively controlled structural system is evaluated by using the frequency-response function and then compared with that of the passively controlled structure to determine the control efficacy. A case study of a 50-story building structure is conducted to illustrate excellent control efficacy of the proposed semi-active MR-TLCD control system.

[1]  Al Dorfmann,et al.  ELASTIC SHEAR FRAMES WITH TUNED LIQUID COLUMN DAMPERS A CONTROLLED STUDY OF SMALL-SCALE MODELS , 2001 .

[2]  Takuji Kobori.  Proceedings of the Second World Conference on Structural Control , 1999 .

[3]  A. Davenport.  The spectrum of horizontal gustiness near the ground in high winds , 1961 .

[4]  Billie F. Spencer,et al.  Large-scale MR fluid dampers: modeling and dynamic performance considerations , 2002 .

[5]  B. Samali,et al.  Control of Along-Wind Response of Structures by Mass and Liquid Dampers , 1992 .

[6]  Ahsan Kareem,et al.  Semi-active tuned liquid column dampers for vibration control of structures , 2001 .

[7]  T. T. Soong,et al.  A STOCHASTIC OPTIMAL SEMI-ACTIVE CONTROL STRATEGY FOR ER/MR DAMPERS , 2003 .

[8]  Wei-Ling Chiang,et al.  Analytical and experimental research on wind-induced vibration in high-rise buildings with tuned liquid column dampers , 2003 .

[9]  Chien Ming Wang,et al.  Effectiveness of tuned liquid column dampers for vibration control of towers , 1995 .

[10]  Yi-Qing Ni,et al.  Smart TLCD using synthetic-hydrocarbon-based MR fluid: an experimental study , 2004, SPIE Smart Structures and Materials + Nondestructive Evaluation and Health Monitoring.

[11]  Thambirajah Balendra,et al.  Effectiveness of TLCD on various structural systems , 1999 .

[12]  S. Yalla,et al.  Optimum Absorber Parameters for Tuned Liquid Column Dampers , 2000 .

[13]  Y. Wen.  Equivalent Linearization for Hysteretic Systems Under Random Excitation , 1980 .

[14]  P. Spanos,et al.  Random vibration and statistical linearization , 1990 .

[15]  Shirley J. Dyke,et al.  An experimental study of MR dampers for seismic protection , 1998 .

[16]  Jonathan W. Bender,et al.  Properties and Applications of Commercial Magnetorheological Fluids , 1999 .

[17]  M. K rn,et al.  Stochastic Optimal Control , 1988 .

[18]  Medhat A. Haroun,et al.  EFFECTIVENESS OF HYBRID LIQUID COLUMN DAMPERS FOR SUPPRESSING STRUCTURAL VIBRATIONS , 2002 .

[19]  B. Samali,et al.  Optimization of tuned liquid column dampers , 1997 .

[20]  Billie F. Spencer,et al.  Semi-Active TLCDS Using Magneto-Rheological Fluids for Vibration Mitigation of Tall Buildings , 2002 .