Torsional vibrations in boxgirder suspension bridges

As you know, suspension bridges are much lighter in their total weight than bridges of other structures. This is their undoubted positive quality. It is no accident that this type of bridge is widely used in practice. However, along with the undeniable advantages, this type of bridge is quite sensitive to wind loads, which are a generator of bending and torsional vibrations of spans at certain speeds of transverse air flow. If the drag of the bridge with a transverse air flow can be easily reduced by designing streamlined surfaces, then ensuring the stability of the bridge span surface for bending and torsion can only be ensured by properly selecting the profile of its cross-section, which provides the necessary moment of inertia, as necessary components of its rigidity.

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Discussion of “Free Torsional Vibrations of Suspension Bridges”

Journal of the Structural Division ◽

10.1061/jsdeag.0005380 ◽

1980 ◽

Vol 106 (2) ◽

pp. 576-577

Author(s):

Hassan I.A. Hegab

Keyword(s):

Suspension Bridges ◽

Torsional Vibrations

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Discussion of “Free Torsional Vibrations of Suspension Bridges”

Journal of the Structural Division ◽

10.1061/jsdeag.0005393 ◽

1980 ◽

Vol 106 (3) ◽

pp. 742-743

Author(s):

Daniel Dicker

Keyword(s):

Suspension Bridges ◽

Torsional Vibrations

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Effect of the main cable bending stiffness on flexural and torsional vibrations of suspension bridges: Analytical approach

Engineering Structures ◽

10.1016/j.engstruct.2021.112393 ◽

2021 ◽

Vol 240 ◽

pp. 112393

Author(s):

Wen-ming Zhang ◽

Xiao-fan Lu ◽

Zhi-wei Wang ◽

Zhao Liu

Keyword(s):

Analytical Approach ◽

Bending Stiffness ◽

Suspension Bridges ◽

Torsional Vibrations ◽

Main Cable

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Control of Vibrations due to Moving Loads on Suspension Bridges

Nonlinear Analysis Modelling and Control ◽

10.15388/na.2006.11.3.14749 ◽

2006 ◽

Vol 11 (3) ◽

pp. 293-318 ◽

Cited By ~ 4

Author(s):

M. Zribi ◽

N. B. Almutairi ◽

M. Abdel-Rohman

Keyword(s):

Bridge Deck ◽

Suspension Bridge ◽

Lyapunov Theory ◽

Dynamic Responses ◽

Suspension Bridges ◽

Control Force ◽

Moving Loads ◽

Hydraulic Actuator ◽

Long Span ◽

Suspended Cables

The flexibility and low damping of the long span suspended cables in suspension bridges makes them prone to vibrations due to wind and moving loads which affect the dynamic responses of the suspended cables and the bridge deck. This paper investigates the control of vibrations of a suspension bridge due to a vertical load moving on the bridge deck with a constant speed. A vertical cable between the bridge deck and the suspended cables is used to install a hydraulic actuator able to generate an active control force on the bridge deck. Two control schemes are proposed to generate the control force needed to reduce the vertical vibrations in the suspended cables and in the bridge deck. The proposed controllers, whose design is based on Lyapunov theory, guarantee the asymptotic stability of the system. The MATLAB software is used to simulate the performance of the controlled system. The simulation results indicate that the proposed controllers work well. In addition, the performance of the system with the proposed controllers is compared to the performance of the system controlled with a velocity feedback controller.

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