Prevention of main cable corrosion by dehumidification

In order to research on mechanical properties of flexible suspension bridges, a geometric nonlinear analysis method was used to simulate on the experimental results, and carried on static loading test finally. In the loading test process, the deformations were measured in critical section of the suspension bridge, and displacement values of measured are compared with simulation values of the finite element simulation. Meanwhile the deformations of the main cable sag are observed under classification loading, the results show that the main cable sag increment is basically linear relationship with the increment of mid-span loading and tension from 3L/8 and 5L/8 to L/2 section, the main cable that increasing unit sag required mid-span loads and tension are gradually reduce in near L/4 and 3L/4 sections and gradually increase in near L/8 and 7L/8 sections and almost equal in near L/2, 3L/8 and 5L/8 sections. From the experimental results, the flexible suspension bridge possess good mechanical properties.

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Main cable dehumidification—flow testing and other innovations

Asset Management of Bridges ◽

10.1201/9780203704486-2 ◽

2017 ◽

pp. 13-28 ◽

Cited By ~ 1

Author(s):

M.L. Bloomstine ◽

J.F. Melén

Keyword(s):

Main Cable

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Research on the Approximate Calculation Method of the Fundamental Frequency and Its Characteristics on a Tensioned String Bridge

Processes ◽

10.3390/pr10010126 ◽

2022 ◽

Vol 10 (1) ◽

pp. 126

Author(s):

Guangwei Zhou ◽

Changzhao Qian ◽

Changping Chen

Keyword(s):

Finite Element ◽

Fundamental Frequency ◽

Vibration Frequency ◽

Structural Characteristics ◽

Physical Characteristics ◽

Parameter Analysis ◽

Lateral Bending ◽

Bending Vibration ◽

Main Cable ◽

Symmetrical Vibration

As a new type of composite bridge, the dynamic structural characteristics of a tensioned string bridge need to be deeply studied. In this paper, based on the structural characteristics of a tensioned string bridge, the Rayleigh method is used to derive formulas for calculating the frequencies of vertical, antisymmetric and lateral bending vibrations. The characteristics of the vertical and lateral bending vibration frequencies are summarized. The fundamental frequencies of the antisymmetric vertical bending and lateral bending of the tensioned string bridge are the same as that of the single-span beam under the corresponding constraint conditions. The shape and physical characteristics of the main cable have no effect on the frequency. The vertical bending symmetrical vibration frequency of the tensioned string bridge is greater than the corresponding symmetrical vibration frequency of the simply supported beam. The shape and physical characteristics of the main cable have a greater impact on the vertical bending symmetrical vibration frequency than the lateral bending frequency, and the vertical bending symmetrical vibration frequency increases with an increasing rise-to-span ratio. The tension force of the main cable has no influence on the frequency of tensioned string bridges. The first-order frequency of the tensioned string bridge is generally the vertical bending symmetrical vibration frequency. By adopting a tensioned string bridge structure, the fundamental frequency of a structure can be greatly increased, thereby increasing the overall rigidity of the structure. Finally, an engineering example is applied with the finite element parameter analysis method to study the vibration frequency characteristics of the tensioned string bridge, which verifies the correctness of the formula derived in this paper. The finite element analysis results show that the errors between the derived formula in this paper and the finite element calculation results are less than 2%, indicating that the formula derived in this paper has high calculation accuracy and can meet the calculation accuracy requirements of engineering applications.

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Wind-Induced Vibration Control of High-Rise Structures Using Compound Damping Cables

Shock and Vibration ◽

10.1155/2021/5537622 ◽

2021 ◽

Vol 2021 ◽

pp. 1-9

Author(s):

Jianda Yu ◽

Zhibo Duan ◽

Xiangqi Zhang ◽

Jian Peng

Keyword(s):

Vibration Control ◽

Damping Ratio ◽

Viscosity Coefficient ◽

Structural Vibration ◽

Vibration Displacement ◽

High Rise ◽

Main Cable ◽

Small Vortex ◽

Wind Induced Vibration ◽

Fluctuating Wind

Based on the vibration reduction mechanism of compound damping cables, this study focuses on the wind-induced vibration control of high-rise structures with additional mass at the top. The differential equation of motion of the system under the action of the composite damping cable is established, and the analytical solution of the additional damping ratio of the structure is deduced, which is verified by model tests. The vibration response of the structure under the action of simple harmonic vortex excitation and randomly fluctuating wind loads is studied, and the effect of different viscous coefficients of the dampers in the composite damping cable and different installation heights of the damping cable on the vibration control is analyzed. The results show that a small vortex excitation force will cause large vibrations of low-dampened towering structures, and the structure will undergo buffeting under the action of wind load pulse force. The damping cable can greatly reduce the amplitude of structural vibration. The root means square of structural vibration displacement varies with damping. The viscosity coefficient of the device and the installation height of the main cable of the damping cable are greatly reduced.

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Experimental Study on Mass Transfer Coefficient of Dry Air in Main Cable of Suspension Bridge

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.461.151 ◽

2012 ◽

Vol 461 ◽

pp. 151-154

Author(s):

Dai Yong Jia ◽

Lu Yan Sui ◽

Ming Lai He

Keyword(s):

Mass Transfer ◽

Transfer Coefficient ◽

Mass Transfer Coefficient ◽

Experimental Studies ◽

Suspension Bridge ◽

Suspension Bridges ◽

Dry Air ◽

Experiment Platform ◽

Main Cable ◽

Key Parameter

In this study, an experiment platform was built up to determine the key parameter, mass transfer coefficient, of the ventilation and dehumidification process in main cable of suspension bridge. On the basis of experimental studies, an empirical formula of the mass transfer coefficient was obtained, which can greatly contribute to control the content of moisture in the main cable of suspension bridges.

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