Structural observation of long-span suspension bridges for safety assessment: implementation of an optical displacement measurement system

The long-span multi-tower suspension bridge is widely used in the construction of river and sea crossing bridges. The load-bearing safety and anti-sliding safety of its main cable are directly related to the structural safety of a suspension bridge. Failure mechanisms of the main cable of a long-span multi-tower suspension bridge are discussed. Meanwhile, the tribo-corrosion-fatigue of main cable, contact, and slip behaviors of the saddle and service safety assessment of the main cable are reviewed. Finally, research trends in service safety assessment of main cable are proposed. It is of great significance to improve the service safety of the main cable and thereby to ensure the structural safety of long-span multi-tower suspension bridges.

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Probability Evaluation Method for Cable Safety of Long Span Suspension Bridges under Extreme Wind Load

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.163-167.3223 ◽

2010 ◽

Vol 163-167 ◽

pp. 3223-3229 ◽

Cited By ~ 1

Author(s):

Jun Hu ◽

Jin Ping Ou

Keyword(s):

Safety Assessment ◽

Evaluation Method ◽

Suspension Bridge ◽

Wind Load ◽

Structural Safety ◽

Suspension Bridges ◽

Type I ◽

Attenuation Relations ◽

Long Span ◽

Extreme Wind

The cable is the main load-bearing component of suspension bridge and its safety assessment under extreme wind load is a key issue to the structure. Take a long-span suspension bridge in the East Sea China as an example, the standard of extreme wind load for structural safety evaluation is established; the wire’s strength model is established by the type I extreme value distribution; cable’s safety assessment function under wind load is established and the Monte Carlo method is used to get the cable’s reliability and reliable indicators. The bridge’s re-service term is taken for 90 years as an example, the results indicate that the wire’s serial effects can’t be ignored, the cable’s reliable indicator decreases as the number of broken wires increases in approximately the linear attenuation relations, the critical percentage of broken wires is about 10%.

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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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