Study of Anticorrosion System and Anticorrosion Mechanism for the Main Cable of Suspension Bridge

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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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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Circumferential Expansion Property of Composite Wrapping System for Main Cable Protection of Suspension Bridge

Advances in Polymer Technology ◽

10.1155/2020/8638076 ◽

2020 ◽

Vol 2020 ◽

pp. 1-18

Author(s):

Pengfei Cao ◽

Hai Fang ◽

Weiqing Liu ◽

Yong Zhuang ◽

Yuan Fang ◽

...

Keyword(s):

Growth Rate ◽

Bearing Capacity ◽

Radial Displacement ◽

Failure Modes ◽

Suspension Bridge ◽

Temperature Deformation ◽

Suspension Bridges ◽

Cross Sectional ◽

Main Cable ◽

Rubber Belt

A composite wrapping system for main cable protection of suspension bridges was designed by using prepreg fiber-reinforced composites and nitrile rubber. The circumferential expansion performance of the system was tested, and the curves of circumferential bearing capacity and radial displacement of the components were obtained. Failure modes of each group of components were compared and analyzed. The results show that most of the components are vertically fractured at the lap transition. The increase of the number of prepreg layers contributed the most to the circumferential bearing capacity of components, with a growth rate of 65.31%~109.01%. The increase of rubber belt layers had the most significant effect on the radial displacement of the components, with a growth rate of 7.06%~23.5%. In the initial stage of the test, the strain of each part of the component was smaller due to the compaction by the loading device, and the strain value of the component was generally linearly increased during the loading process, during which the strain of the overlap was the smallest. The calculated cross-sectional temperature deformation of the main cable is in good agreement with the experimental data. The application of the rubber belt increases the deformation of the main cable; therefore, the protection system for the main cable could have more deformation redundancy and delay the arrival of the ultimate strain of the outer prepreg wrap.

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Analytic Methods of Main Cable Initial Curve Calculation in Variable Temperature Field

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.163-167.307 ◽

2010 ◽

Vol 163-167 ◽

pp. 307-312

Author(s):

Xiang Ren

Keyword(s):

Temperature Field ◽

Variable Temperature ◽

Suspension Bridge ◽

Horizontal Component ◽

Length Variation ◽

Calculation Methods ◽

Initial Curve ◽

Temperature Changes ◽

Main Cable ◽

Cable Forces

In order to study temperature effect on initial curve of main cable, three different temperature models were built about temperature changes of main cable along span direction, and iteration calculation methods to find initial curve of main cable in variable temperature field was proposed based on the theory that the length of non-stress wire strand is persistence in unloaded cable station and construction completion station. The catenary equation in variable temperature field was deduced and the suspender length variation as well as horizontal component of cable forces were calculated based on the catenary equation. Taking some suspension bridge for an example, suspender length variation, horizontal component of the cable forces and node coordinate under three different temperature models were calculated by iteration calculation methods.

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Application of Exact Element-Method on Calculation of Form-Finding and Unstressed Length of Cable

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.405-408.1699 ◽

2013 ◽

Vol 405-408 ◽

pp. 1699-1708

Author(s):

Zhou Li ◽

Yuan Cheng Wei ◽

Rong Hui Wang ◽

Jia Lun Li ◽

Peng Zhang

Keyword(s):

Finite Element ◽

Solution Process ◽

Suspension Bridge ◽

Equilibrium Relation ◽

Form Finding ◽

Finite Element Software ◽

Main Cable ◽

Computational Procedures ◽

Shape Curve ◽

Element Method

The problem of form-finding for the suspended cable is actually the problem of determining all key points coordinates on main cable, which are by equilibrium relation on the horizontal force, main cable sagitta and lifting point force under the precondition of determining the endpoints boundary conditions of cable segment. According from the static equilibrium relationship of cable element, based on the analysis of its analytical solution process, in this paper, the cable elements are divided into two types in accordance withthe vertical distribution load along the arc length and along the string length , the corresponding shape curve of cable element is the parabola and the catenary, and with parabolic results as its initial value for the iteration of nonlinear solution, then cable element eventually converge for the catenary. And based on the exact coordinates results ,the calculation method of the length without stress is presented,and compiled corresponding computational procedures. By comparing the results of form-finding and the cable-length in non-stress according to program compiled and the results from the finite element software and the measured value of Aizhai suspension bridge, compared with the nonlinear finite element method,it confirmed the method requireing smaller dividing element density, the convergence speed is quicker and the results can ensure the precision.

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Parametric Study on Responses of a Self-Anchored Suspension Bridge to Sudden Breakage of a Hanger

The Scientific World JOURNAL ◽

10.1155/2014/512120 ◽

2014 ◽

Vol 2014 ◽

pp. 1-10 ◽

Cited By ~ 6

Author(s):

Wenliang Qiu ◽

Meng Jiang ◽

Cailiang Huang

Keyword(s):

Suspension Bridge ◽

Element Model ◽

Dynamic Responses ◽

Flexural Stiffness ◽

Static And Dynamic Analysis ◽

Main Cable ◽

Reaction Forces ◽

Internal Forces ◽

Torsion Stiffness ◽

Main Cables

The girder of self-anchored suspension bridge is subjected to large compression force applied by main cables. So, serious damage of the girder due to breakage of hangers may cause the collapse of the whole bridge. With the time increasing, the hangers may break suddenly for their resistance capacities decrease due to corrosion. Using nonlinear static and dynamic analysis methods and adopting 3D finite element model, the responses of an actual self-anchored suspension bridge to sudden breakage of hangers are studied in this paper. The results show that the sudden breakage of a hanger causes violent vibration and large changes in internal forces of the bridge. In the process of the vibration, the maximum tension of hanger produced by breakage of a hanger exceeds 2.22 times its initial value, and the reaction forces of the bearings increase by more than 1.86 times the tension of the broken hanger. Based on the actual bridge, the influences of some factors including flexural stiffness of girder, torsion stiffness of girder, flexural stiffness of main cable, weight of girder, weight of main cable, span to sag ratio of main cable, distance of hangers, span length, and breakage time of hanger on the dynamic responses are studied in detail, and the influencing extent of the factors is presented.

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