In order to overcome long span cables vibration, a calculation model for the cable-damper system was formulated by Galerkin method based on the Hamilton principle. The motion of the cable was computed by using a finite series approximation with a Galerkin method. Runge-Kutta method was applied for the numerical solution of initial value problems with oscillating solutions.A static deflection shape was taken as an addition shape function to improve the sine series convergence. According to experimental set-up, the 154 m long cable in the 3th Qianjiang Cable Stayed Bridge was numerical calculated. A nonlinear hysteretic bi-viscous model was identified for MR dampers. The displacement signal at observation point was driven by harmonic planar loads, and transformed by Hilbert. The equivalent cable modal damping ratios attributed to MR dampers were predicted, and the relationship among the equivalent modal damping ratios, the system frequency, the voltage imposed and displacement responses at the point of cable was pursued.The phenomena and conclusions from simulation guiding the experimental operation could be certified by full scale experimental study. It is shown that MR dampers to the cable can more significantly reduce cable vibration than oil dampers do; the resonant frequencies of the cable with MR dampers have a little increased change; there is optimum voltage on which the maximum modal damping ratio can be achieved.
Key words
bridge engineering /
stay cable /
numerical simulation /
magnetorheological damper /
vibration control
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References
[1] MICHEL V.Recent Evolution of Cable-Stayed Bridges[J].Engineering Structures, 1999, 21(8):737-755.
[2] 王修勇, 陈政清, 倪一清, 等.斜拉桥拉索磁流变阻尼器减振技术研究[J].中国公路学报, 2003, 16(2):52-56.
[3] 陈 勇, 楼文娟.斜拉桥拉索的振动及控制现场试验[J].长安大学学报:自然科学版, 2003, 23(2):48-51.
[4] 陈水生.斜拉桥拉索的MR半主动控制研究[J].中国公路学报, 2004, 17(2):50-54.
[5] 邬喆华, 陈 勇, 楼文娟, 等.磁流变阻尼器对斜拉索减振效果的试验研究[J].振动工程学报, 2004, 17(1):102-107.
[6] 李 惠, 刘 敏, 欧进萍, 等.斜拉索磁流变智能阻尼控制系统分析与设计[J].中国公路学报, 2005, 18(4):37-41.
[7] 李以农, 郑 玲.基于微分几何理论的汽车半主动悬架非线性振动控制[J].中国公路学报, 2005, 18(1):109-112.
[8] NI Y Q, LOU W J, KO J M.A Hybrid Pseudo-Force/Laplace Transformation Method for Non-linear Transient Response of a Suspended Cable[J].Journal of Sound and Vibration, 2000, 238(2):189-214.
[9] JOHNSON E A, SPENCER B F, FUJINO Y, et al.Semiactive Damping of Stay Cables:a Preliminary Study[C]//Society for Experimental Mechanics.Proceedings of the 17th International Modal Analysis Conference.Bethel:Society for Experimental Mechanics, 1999:417-423.
[10] RICHARD E, CHRISTENSON B S.Semiactive Con-trol of Civil Structures for Natural Hazard Mitigation Analytical and Experimental Studies[D].Notre Dame:The University of Notre Dame, 2001.
[11] NI Y Q.Experimental Study and Modelling of Magnetorheological Damper[D].Hong Kong:The Hong Kong Polytechnic University, 2001.
[12] SIMOS T E. Some Modified Runge-Kutta Methods for the Numerical Solution of Initial-Value Problems with Oscillating Solutions[J].Journal of Scientific Computing, 1998, 13(1):51-62.
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Footnotes
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