scholarly journals The USGT Method for Suspender Tensioning of Self-Anchored Suspension Bridges

2021 ◽  
Vol 2021 ◽  
pp. 1-10
Author(s):  
Hongmei Tan ◽  
Zhujian Hou ◽  
Zhou Qiu ◽  
Junlin Ji ◽  
Dahan Chen
Keyword(s):  
Composite Beam ◽  
Bending Moment ◽  
Combination Method ◽  
Main Beam ◽  
Suspension Bridges ◽  
Construction Process ◽  
Finite Element Software ◽  
Main Cable ◽  
Unstrained State ◽  
State Method

Unlike earth-anchored suspension bridges, self-anchored suspension bridges (SASBs) involve a special construction stage, namely, suspender tensioning, in which the tensioning force and sequence are crucial and complicated. Against this background, an example bridge A, a SASB with a steel-concrete composite beam, is introduced in detail. Using MIDAS finite element software, a suspender tensioning scheme is formulated based on a combination method of the unstrained state method and graded tension method (the USGT method), in which a suspender is tensioned according to its unstrained length. By analyzing the bending moment change of the beam and deflection of the main cable throughout the entire construction process, a “high-to-low” suspender tensioning sequence is proposed that also involves symmetrical tensioning from the main towers to the midspan or the anchor positions. In the optimized construction process, the deviation and stress of the main towers are controlled well, thereby ensuring the safety of the main beam and main towers in the construction process.

scholarly journals Simplified Analytical Method for Optimized Initial Shape Analysis of Self-Anchored Suspension Bridges and Its Verification

2015 ◽  
Vol 2015 ◽  
pp. 1-14 ◽  
Author(s):  
Myung-Rag Jung ◽  
Dong-Ju Min ◽  
Moon-Young Kim
Keyword(s):  
Analytical Method ◽  
Bending Moment ◽  
Suspension Bridge ◽  
Suspension Bridges ◽  
Equilibrium Equations ◽  
Initial State ◽  
Initial Shape ◽  
Main Cable ◽  
Initial Shape Analysis ◽  
Bridge Models

A simplified analytical method providing accurate unstrained lengths of all structural elements is proposed to find the optimized initial state of self-anchored suspension bridges under dead loads. For this, equilibrium equations of the main girder and the main cable system are derived and solved by evaluating the self-weights of cable members using unstrained cable lengths and iteratively updating both the horizontal tension component and the vertical profile of the main cable. Furthermore, to demonstrate the validity of the simplified analytical method, the unstrained element length method (ULM) is applied to suspension bridge models based on the unstressed lengths of both cable and frame members calculated from the analytical method. Through numerical examples, it is demonstrated that the proposed analytical method can indeed provide an optimized initial solution by showing that both the simplified method and the nonlinear FE procedure lead to practically identical initial configurations with only localized small bending moment distributions.

Object-Oriented Computer-Aided Analysis for Construction Control of Anchored Suspension Bridge

2014 ◽  
Vol 543-547 ◽  
pp. 3977-3981
Author(s):  
Jian Yuan Sun ◽  
Cheng Zhang Yin ◽  
Zeng Bao Ma
Keyword(s):  
Safety Margin ◽  
Object Oriented ◽  
Suspension Bridge ◽  
High Accuracy ◽  
Object Oriented Programming ◽  
Suspension Bridges ◽  
Construction Control ◽  
Control Analysis ◽  
Finite Element Software ◽  
Main Cable

With the increase of the span of suspension bridge, the weight of the main cable increases, and the safety margin becomes smaller. Thus high accuracy is necessary for the construction control analysis of suspension bridges. The traditional finite element software cannot meet the accuracy requirement because of temperature, cable saddle and other factors, which influence the construction control. Based on the modified segmental catenary method, this paper has come up with a fine analysis method for the construction control of suspension bridges. And a software program called ZambisSC has been developed using object-oriented programming language combined with a number of the latest software development technologies. Compared with the monitoring results of Nancha suspension bridge in Guangzhou, China, it shows that ZambisSC can predict the main cable shape with high accuracy.

Calculation and Analysis of the Construction Program in Nanjing Rail Transit Line 1 from South Yanande's Door to NingDan Road

2012 ◽  
Vol 256-259 ◽  
pp. 1447-1452
Author(s):  
Ying Chun Fu
Keyword(s):  
Ground Surface ◽  
Bending Moment ◽  
Surface Settlement ◽  
Tunnel Construction ◽  
Rail Transit ◽  
Construction Process ◽  
Finite Element Software ◽  
Ground Surface Settlement ◽  
Subway Construction ◽  
Supporting Force

It is the key to success or failure of the construction that we control the ground surface settlement, vault sink and supporting force by the choice of the reasonable construction method in the subway construction process. Based on the project profiles of the tunnel in Nanjing orbit traffic line 1 from South Yan'an road to NingDan road, the article mainly carries on the numerical simulation to construction program by using ANSYS finite element software according to the joint arch tunnel construction of the double and triple arch in the entry end .The article mainly has an analysis from the ground surface settlement, the strata, axial force of supporting structure, bending moment and other aspects. The results show that the program is feasible. The article provids guidance to the future construction of similar projects .

An analytical algorithm for the pylon saddle pushing stage and distance during the suspension bridge construction

2019 ◽  
Vol 22 (15) ◽  
pp. 3290-3305
Author(s):  
Wen-ming Zhang ◽  
Kai-rui Qian ◽  
Gen-min Tian ◽  
Zhao Liu
Keyword(s):  
Stress State ◽  
Proper Time ◽  
Bending Moment ◽  
Strength Criterion ◽  
Suspension Bridge ◽  
Suspension Bridges ◽  
Bridge Construction ◽  
Main Cable ◽  
Analytical Algorithm ◽  
Tensile Forces

During the construction of suspension bridges, the stress state of the pylon (tower) is improved by pushing the pylon saddle by an appropriate distance at the proper time. An analytical algorithm for the assessment of the required timing and displacements for the pylon saddle pushing at particular construction stages is proposed and verified in this study. The timing calculation is based on the assessment of current hanger tensile forces at each construction stage and the pylon stress state, while the pushing distance/displacement is derived from the conditions of elevation difference closure and the conservation of unstrained length of the main cable segments. This algorithm was successfully applied during the construction of a particular suspension bridge in China with a main span of 730 m. The results obtained strongly indicate that the bending moment in the pylon bottom is contributed by both horizontal and vertical forces of the main cable. The horizontal constituent is dominant and its share gradually increases in the bridge construction process. In a suspension bridge with side spans of various lengths, the stresses in the pylon bottom on the side with a larger side span is more likely to exceed the limit. Therefore, the respective strength criterion controls the pylon saddle-pushing schedule. The proposed analytical algorithm is quite straightforward and is recommended for wider application.

Analysis and Test on Mechanical Properties of a Flexible Suspension Bridge

2013 ◽  
Vol 405-408 ◽  
pp. 1616-1622
Author(s):  
Guo Hui Cao ◽  
Jia Xing Hu ◽  
Kai Zhang ◽  
Min He
Keyword(s):  
Mechanical Properties ◽  
Suspension Bridge ◽  
Experimental Results ◽  
Suspension Bridges ◽  
Loading Test ◽  
Main Cable ◽  
Element Simulation ◽  
Static Loading Test ◽  
Geometric Nonlinear Analysis ◽  
Test Process

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.

Finite Element Analysis on Incremental Launching Construction for Steel Box Girder

2013 ◽  
Vol 671-674 ◽  
pp. 974-979
Author(s):  
Jie Dai ◽  
Jin Di ◽  
Feng Jiang Qin ◽  
Min Zhao ◽  
Wen Ru Lu
Keyword(s):  
Finite Element ◽  
Bending Moment ◽  
Internal Force ◽  
Element Analysis ◽  
Box Girder ◽  
Finite Element Software ◽  
Cable Stayed Bridge ◽  
Steel Box Girder ◽  
Maximum Value ◽  
Negative Bending

For steel box girder of cable-stayed bridge, which using incremental launching method, during the launching process, structural system and boundary conditions were changing, structure mechanical behaviors were complex. It was necessary to conduct a comprehensive analysis on internal force and deformation of the whole structure during the launching process. Took a cable-stayed bridge with single tower, double cable planes and steel box girder in China as an example; finite element software MIDAS Civil 2010 was used to establish a model for steel box girder, simulation analysis of the entire incremental launching process was carried out. Variation rules and envelopes of the internal force, stress, deformation and support reaction were obtained. The result showed that: the maximum value of positive bending moment after launching complete was 60% of the maximum value of positive bending moment during the launching process. The maximum value of negative bending moment after launching complete was 78% of the maximum value of negative bending moment during the launching process.

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

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.

scholarly journals The new bud light steel system and the geometric shape evolution of light steel framework for COVID-19 patients appointed hospital (Huoshenshan hospital)

2020 ◽  
Vol 39 (6) ◽  
pp. 9015-9026
Author(s):  
Lilin Wang
Keyword(s):  
Simulation Analysis ◽  
Steel Structure ◽  
Model Material ◽  
Construction Process ◽  
Actual Measurement ◽  
Finite Element Software ◽  
Whole Process ◽  
Long Time ◽  
The Common ◽  
Actual Size

The light steel structure is always the common material of the movable plank house, and the new bud light steel system is the light steel system used for a long time after the earthquake. This paper discusses the mechanical system of the light steel structure of Huoshenshan hospital, which was built in ten days. In the process of building, the geometric form of roof stress has changed. In the actual structural design, the designer seldom takes the calculation of construction load into account, which is quite different from the actual construction process. So it is very important to simulate and monitor the whole process of structure installation. In this paper, the finite element software MIDAS / Gen is used for simulation analysis to ensure that the simulation analysis results are consistent with the construction process, the model material and the actual size are completely consistent, and the stress simulated by the software can meet the needs of the actual stress through the actual measurement.

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

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.

Sign in / Sign up

Export Citation Format

Share Document