The Second Maintenance and Strengthening of Yonghe Bridge

2011 ◽  
Vol 90-93 ◽  
pp. 1074-1081 ◽  
Author(s):  
Hong Jiang Li
Keyword(s):  
Safety Factor ◽  
Prestressed Concrete ◽  
Line Shape ◽  
Structural System ◽  
Stay Cable ◽  
Cable Stayed Bridge ◽  
Load Combination ◽  
Cable Forces ◽  
Main Girder ◽  
Cable Stayed Bridges

Tension rocker bearing (TRB) cables installed at auxiliary piers were critical members to sustain the structural system in a prestressed concrete cable-stayed bridge. Once these cables fractured or broken, its structural system would be transferred. Based on diseases caused by fracture of TRB cables in Yonghe Bridge, corresponding maintenance or strengthening measures were described in detail. These measures included replacement of TRB cables, strengthening of the closure segment of main girder at each side span, and adjustment of stay cable forces. Monitoring results showed that, its structural system was finally and completely rehabilitated, and the safety factor of new TRB cables is enough under the most unfavorable load combination. Moreover, the line shape of main girder and the inclined displacement at the top of each pylon were improved effectively. Thus, Yonghe Bridge accumulated some valuable experience for maintenance or strengthening of existing prestressed concrete cable-stayed bridges, and also made a useful exploration.

A prediction method for cable forces of cable-stayed bridges using fuzzy processing and Bayes estimation

2021 ◽  
Author(s):  
Li Dong ◽  
Bin Xie ◽  
Dongli Sun ◽  
Yizhuo Zhang
Keyword(s):  
Prediction Method ◽  
Practical Method ◽  
Bayes Estimation ◽  
Primary Data ◽  
Force Estimation ◽  
Element Analysis ◽  
Cable Stayed Bridge ◽  
Input Parameters ◽  
Cable Forces ◽  
Cable Stayed Bridges

<p>Cable forces are primary factors influencing the design of a cable-stayed bridge. A fast and practical method for cable force estimation is proposed in this paper. For this purpose, five input parameters representing the main characteristics of a cable-stayed bridge and two output parameters representing the cable forces in two key construction stages are defined. Twenty different representative cable-stayed bridges are selected for further prediction. The cable forces are carefully optimized through finite element analysis. Then, discrete and fuzzy processing is applied in data processing to improve their reliability and practicality. Finally, based on the input parameters of a target bridge, the maximum possible output parameters are calculated by Bayes estimation based on the processed data. The calculation results show that the average prediction error of this method is less than 1% for the twenty bridges themselves, which provide the primary data and less than 3% for an under-construction bridge.</p>

Aesthetic Design of Odawara Port Bridge

1996 ◽  
Vol 1549 (1) ◽  
pp. 108-113
Author(s):  
Tsuguo Oishi ◽  
Yasuo Inokuma
Keyword(s):  
Cross Section ◽  
Prestressed Concrete ◽  
Surrounding Area ◽  
Box Girder ◽  
Aesthetic Design ◽  
Cable Stayed Bridge ◽  
The World ◽  
Bridge Type ◽  
Main Girder ◽  
Tower Height

The Odawara Port Bridge is located at the mouth of Odawara Port. Selecting a bridge type that symbolized the entire project and blended well with the surrounding area was critical. To achieve this, an extra-dosed prestressed concrete box girder with a main span of 122 m was selected. Construction of this bridge type is the first in the world. Special characteristics of this bridge type are a lower tower height than that of a cable-stayed bridge, the use of a saddle at the top of the towers, and the incorporation of epoxy-coated strands for diagonal cables. The design of the various sections of the bridge was achieved by integrating the characteristic shape of the towers with cable profiles while establishing horizontal continuity with the main girder. As a result of the integration process, the following design objectives were adopted: (a) constant main girder depth; (b) inverted trapezoidal main girder cross section; (c) towers without a connecting beam at the top; (d) a fan-shaped saddle; (e) compact cable vibration dampers; (f) graded metallic coloring of cables; (g) integrated steel railing and road surface lighting; (h) nighttime bridge lighting, and (i) encased drainage pipes.

Monitored structural behavior of a long span cable-stayed bridge under environmental effects

2018 ◽  
Vol 4 (4) ◽  
pp. 137 ◽  
Author(s):  
Alemdar Bayraktar ◽  
Ashraf Ashour ◽  
Halil Karadeniz ◽  
Altok Kurşun ◽  
Arif Erdiş
Keyword(s):  
Air Temperature ◽  
Environmental Effects ◽  
Monitoring Data ◽  
Structural Behavior ◽  
Steel Cable ◽  
Daily Monitoring ◽  
Cable Stayed Bridge ◽  
Long Span ◽  
Cable Forces ◽  
Cable Stayed Bridges

An accurate numerical analysis of the behavior of long-span cable-stayed bridges under environmental effects is a challenge because of complex, uncertain and varying environmental meteorology. This study aims to investigate in-situ experimental structural behavior of long-span steel cable-stayed bridges under environmental effects such as air temperature and wind using the monitoring data. Nissibi cable-stayed bridge with total length of 610m constructed in the city of Adıyaman, Turkey, in 2015 is chosen for this purpose. Structural behaviors of the main structural elements including deck, towers (pylons) and cables of the selected long span cable-stayed bridge under environmental effects such as air temperature and wind are investigated by using daily monitoring data. The daily variations of cable forces, cable accelerations, pylon accelerations and deck accelerations with air temperature and wind speed are compared using the hottest summer (July 31, 2015) and the coldest winter (January 1, 2016) days data.

Analysis on Reasonable Structure of Main Girder of Harp Shaped Cable-Stayed Bridge without Backstays

2011 ◽  
Vol 90-93 ◽  
pp. 1061-1068
Author(s):  
Ai Jun Chen ◽  
Guo Jing He
Keyword(s):  
Design Parameters ◽  
Bridge Design ◽  
Structure Selection ◽  
Cable Stayed Bridge ◽  
Design Philosophy ◽  
Section Design ◽  
Selection For ◽  
Main Girder ◽  
Cable Stayed Bridges

Harp shaped cable-stayed bridges without backstays are popular due to their beautiful and unique styles; they employ leaning tower columns to balance the constant and movable loads on the decks and are not provided with backstays, so they are beyond the traditional bridge design philosophy. In this paper, we discussed the reasonable structure of the main girder of Changsha Hongshan Bridge – a harp shaped cable-stayed bridge without backstays through changing the design parameters of the main girder in respect of design so as to provide important reference for design of this kind of bridges, and the research mainly related to such aspects as the structure selection for and section design of the main girder, the influence of overweight of main girder on the force on the structure, the length of non-cable area of the main girder, the span of auxiliary hole, etc.

Analysis on Stiff Frame in Replacement of Closure Segment for Prestressed Concrete Cable-Stayed Bridges

2013 ◽  
Vol 351-352 ◽  
pp. 1423-1431
Author(s):  
Hong Jiang Li ◽  
Da Yi Lu ◽  
Qi Feng Wang
Keyword(s):  
Prestressed Concrete ◽  
Calculation Method ◽  
Design Calculation ◽  
Working Process ◽  
Structural Dynamic ◽  
Internal Forces ◽  
Stage Analysis ◽  
Main Girder ◽  
Compression Member ◽  
Cable Stayed Bridges

Stiff frame was the important structural member in construction of replacement of closure segment for prestressed concrete cable-stayed bridges. To establish the design calculation method of it and reveal its variation of internal forces with construction stages of replacement, some configurations and its working process of stiff frame was introduced. Based on construction stage analysis of replacement, calculation methods of its strength and stability were given. Through FEM results, influence of stiff frame to structural dynamic property and global stability of whole bridge were described. Analysis results showed, it was appropriate to consider each section steel of stiff frame as eccentric compression member. During construction, the transversal global property of stiff frame and the security of its link with main girder must be valued. Construction results also proved, the theoretical calculation method could reflect the actual structural state of stiff frame, and its result was conservative. Analysis on stiff frame was an important part of replacement of closure segment, and could provide ways and references for construction control of replacement of closure segment.

scholarly journals UNCONVENTIONAL DOUBLE-LEVEL STRUCTURAL SYSTEM FOR UNDER-DECK CABLE-STAYED BRIDGES

2012 ◽  
Vol 18 (3) ◽  
pp. 436-443 ◽  
Author(s):  
Ieva Misiunaitė ◽  
Alfonsas Daniūnas ◽  
Algirdas Juozapaitis
Keyword(s):  
Linear Analysis ◽  
Computational Method ◽  
Structural System ◽  
Comparison Analysis ◽  
Simply Supported ◽  
Deformation Response ◽  
Cable Stayed Bridge ◽  
Asymmetric Loading ◽  
Correct Implementation ◽  
Cable Stayed Bridges

This paper presents a new morphology of a cable-staying system for an under-deck cable-stayed bridge. The computational method proposed in the paper has been derived for a one-strut conventional cable staying system and applied for an unconventional double-level cable-staying system. The paper describes an algorithm for the correct implementation of the interaction between the cable-staying system and the deck. The numerical examples demonstrate that the proposed computational method based on a non-linear analysis of a simply supported and additionally restrained beam-column can be used for obtaining deformation response to the considered structure. An analysis of the same problem using finite element (FE) software ANSYS was carried out to present the accuracy of the proposed method. The paper also demonstrates comparison analysis between the conventional and unconventional structural schemes for the under-deck cable-stayed bridge under symmetric and asymmetric loading.

Novelty detection of cable-stayed bridges based on cable force correlation exploration using spatiotemporal graph convolutional networks

2021 ◽  
pp. 147592172098866
Author(s):  
Shunlong Li ◽  
Jin Niu ◽  
Zhonglong Li
Keyword(s):  
Novelty Detection ◽  
The State ◽  
Spatial Dependency ◽  
Sensor Fault ◽  
Spatiotemporal Model ◽  
Convolutional Networks ◽  
Cable Stayed Bridge ◽  
Adjacency Matrices ◽  
Cable Forces ◽  
Cable Stayed Bridges

The novelty detection of bridges using monitoring data is an effective technique for diagnosing structural changes and possible damages, providing a critical basis for assessing the structural states of bridges. As cable forces describe the state of cable-stayed bridges, a novelty detection method was developed in this study using spatiotemporal graph convolutional networks by analysing spatiotemporal correlations among cable forces determined from different cable dynamometers. The spatial dependency of the sensor network was represented as a directed graph with cable dynamometers as vertices, and a graph convolutional network with learnable adjacency matrices was used to capture the spatial dependency of the locally connected vertices. A one-dimensional convolutional neural network was operated along the time axis to capture the temporal dependency. Sensor faults and structural variations could be distinguished based on the local or global anomalies of the spatiotemporal model parameters. Faulty sensors were detected and isolated using weighted adjacency matrices along with diagnostic indicators of the model residuals. After eliminating the effect of the sensor fault, the underlying variations in the state of the cable-stayed bridge could be determined based on the changing data patterns of the spatiotemporal model. The application of the proposed method to a long-span cable-stayed bridge demonstrates its effectiveness in sensor fault localization and structural variation detection.

scholarly journals Designing and 3-D Modelling of a Sustainable Cable Stayed Bridge-A Case Study

2020 ◽  
Vol 220 ◽  
pp. 01070
Author(s):  
Priyanka Singh ◽  
Mirza Jahangir Baig ◽  
Bhumika Pandey ◽  
Kartik Papreja
Keyword(s):  
The Past ◽  
Cable Stayed Bridge ◽  
Symmetrical Design ◽  
The World ◽  
Tensile Forces ◽  
Cable Forces ◽  
Design Options ◽  
World Development ◽  
Cable Stayed Bridges

In the world of Civil Engineering, bridges are an example of structural art expressing how much the structures have evolved till present times. The concept and design of bridges has been evolved over the past years, having numerous amounts of different geometrical models and methods to construct bridges. As the development and innovation has reached so far, the concept of bridges has made a great impact on global infrastructure by creating sustainable, effective, and aesthetical bridges around the world. development of the finest aesthetical and sustainable designs for bridges which are known as Cable Stayed BridgesThe bridge form in which the weight of the deck is supported by a number of nearly straight diagonal cables in tension running directly to one or more vertical towers. The towers transfer the cable forces to the foundations through vertical compression. The tensile forces in the cables also put the deck into horizontal compression. Cable stayed bridges are the types of bridges those are best suited for connecting wide-span crossings. Construction of cable stayed bridge is widely promoted all over the world and construction of more than 600 cable stayed bridges are recorded till date. This type of bridge is preferred over any other type due to its possible construction to the indefinite length, availability of multiple design options with the possibility of symmetrical design and excellent strength. In this paper we shall discuss numerous case studies of the cable stayed bridges, compile all the beneficial data for most of the cable stayed bridges located in India.

Conceptual Design of balanced Cable-Stayed Bridges

2019 ◽  
Author(s):  
Sami Soppela ◽  
Esko Järvenpää
Keyword(s):  
Longitudinal Direction ◽  
Design Stage ◽  
Span Length ◽  
Early Design Stage ◽  
Cable Stayed Bridge ◽  
Permanent Load ◽  
Live Loads ◽  
Cable Forces ◽  
Optimum Solution ◽  
Cable Stayed Bridges

<p>The cables are the major loadbearing cost components in the longitudinal direction of a cable-stayed bridge. The quantity of the cables reflects directly to the comparative costs of different alternative layouts. The cable forces, calculated for permanent load balance lead to a reliable cable quantity estimation. For a long-term durability it is important that the bridge is in balance for permanent loads. The influence of the live loads can be estimated separately.</p><p>The purpose of this article is to estimate cable quantities in an early design stage when finding the optimum solution for the bridge. A simple solution method is carried out mathematically using vector algebra and the force length method. This article sets a clear path for determining the preliminary cable forces and cable quantities for two-pylon and single-pylon cable-stayed bridges. The variables are the span length relation, pylon height relation to the main span length, optimum cable anchorage distance at the pylon and the permanent load of the deck.</p><p>Also, the cable quantities of single-pylon bridges can be calculated, even for bridges with highly asymmetric spans. It is noted that the single-pylon cable-stayed bridge has remarkably bigger cable quantity than the two- pylon bridge with equal length.</p><p>The results reveal that the optimum cable anchorage distance in the pylon depends on the pylon height. The higher the pylon is, the greater the optimum anchorage distance should be.</p><p>For the durable bridge an optimum layout and a good balance for gravity loads with minimized bending moments are an important design target. The article helps in reaching that target.</p>

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