Bearing Capacity Analysis of Transmission Tower Structure Considering Corrosion Damage

Abstract As an important part of power grid equipment, transmission towers are in direct contact with the external environment for a long time. As a coastal city in China, Fujian has been affected by marine environment and industrial pollution for a long time, which directly affects the safety of transmission towers in long-term service. In order to explore the changes of the ultimate bearing capacity of the tower structure after corrosion, this paper uses finite element software to analyse the mechanical properties of the tower structure during long-term service, and finds that the 45° wind direction is the control condition, and the overall stiffness of the tower decreases with the growth of corrosion time, and the increment of tower top displacement reaches 7% at 12 years of corrosion. The corrosion-sensitive members of the tower were clearly identified, and their stress ratios increased from 0.78, 0.79, and 0.83 to 0.97, 0.98, and 0.99, respectively, at 12 years of corrosion.

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Collapse Analysis of a Transmission Tower-Line System Induced by Ice Shedding

Frontiers in Physics ◽

10.3389/fphy.2021.712161 ◽

2021 ◽

Vol 9 ◽

Author(s):

Jiaxiang Li ◽

Biao Wang ◽

Jian Sun ◽

Shuhong Wang ◽

Xiaohong Zhang ◽

...

Keyword(s):

Finite Element ◽

Transmission Lines ◽

Progressive Collapse ◽

Element Model ◽

Transmission Tower ◽

Line System ◽

Finite Element Software ◽

Transmission Towers ◽

Ice Shedding ◽

The Impact

Ice shedding causes transmission lines to vibrate violently, which induces a sharp increase in the longitudinal unbalanced tension of the lines, even resulting in the progressive collapse of transmission towers in serious cases, which is a common ice-based disaster for transmission tower-line systems. Based on the actual engineering characteristics of a 500 kV transmission line taken as the research object, a finite element model of a two-tower, three-line system is established by commercial ANSYS finite element software. In the modeling process, the uniform mode method is used to introduce the initial defects, and the collapse caused by ice shedding and its influencing parameters are systematically studied. The results show that the higher the ice-shedding height is, the greater the threat of ice shedding to the system; furthermore, the greater the span is, the shorter the insulator length and the greater the dynamic response of the line; the impact of ice shedding should be considered in the design of transmission towers.

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Research on Application of Non-Equilateral Angle Steel for Transmission Towers

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.459.589 ◽

2013 ◽

Vol 459 ◽

pp. 589-594

Author(s):

Yu Zhuo Jia ◽

Hai Hong Xi ◽

Liang Zhang

Keyword(s):

Large Scale ◽

Working Condition ◽

Transmission Tower ◽

Cross Sectional ◽

Short Side ◽

Finite Element Software ◽

Transmission Towers ◽

Angle Steel ◽

Research On Application ◽

Bolt Connection

In Chinese transmission towers, all the steels are equilateral angle, most of the diagonal and secondary members are in one-sided bolt connection working condition, so the force is eccentric. When the length within a certain range, relative to the equilateral angle, non-equilateral angle steel under this working condition to be able to withstand a larger load, and the ability to cross-sectional area smaller, reducing the weight of the whole base tower. In order to solve the above problems, through research and analysis of large-scale finite element software ANSYS diagonal and secondary members for transmission tower angle steel model length which can be equilateral angle replaced non-equilateral angle steel. Eventually found that when the length is small long side is connected to non-equilateral angle steel are available, and when the length is bigger short side is connected to non-equilateral angle steel are available.

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A Real-Time Reliable Condition Assessment System for 500kV Transmission Towers Based on Stress Measurement

Mathematical Problems in Engineering ◽

10.1155/2019/3241897 ◽

2019 ◽

Vol 2019 ◽

pp. 1-8

Author(s):

Zhi-xiong Liu ◽

Xiao-bo Feng

Keyword(s):

Real Time ◽

Stress Measurement ◽

Condition Assessment ◽

Assessment System ◽

Assessment Procedure ◽

Transmission Power ◽

Transmission Tower ◽

Application Systems ◽

Transmission Towers ◽

Tower Structure

Transmission power towers play an important role in power delivery systems. In recent years, some important results on reliability of transmission towers have been obtained based on theoretical analysis, but there are very few practical application systems of real-time condition monitoring. This paper proposes a new real-time reliable condition assessment system for 500kV transmission power towers based on stress measurement. The necessity of such systems and the architecture of the online monitoring system will first be presented. Through calculating the stress distribution condition of different components of the transmission tower under typical working conditions, those positions with relatively high failure probability in the transmission tower can be identified monitored for installing the stress sensors on them. A new method is presented for calculating the reliability index of the transmission tower structure is also developed based on the mechanical structure of the tower. In particular, the tower structure is simplified to a series system, and the Ditlevsen’s bounds is used to estimate the reliability of the tower system. Finally, a designed example for the online reliable condition assessment procedure is given using a 500kV oxytropis tower as an illustration.

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Analysis on Ultimate Bearing Capacity of the UHV Transmission Tower with Large Width Angle Steel

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.405-408.786 ◽

2013 ◽

Vol 405-408 ◽

pp. 786-789

Author(s):

Qi Xiao ◽

Dan Dan Tong ◽

Ling Feng Song

Keyword(s):

Finite Element ◽

Bearing Capacity ◽

Element Model ◽

Ultimate Bearing Capacity ◽

Transmission Tower ◽

Future Design ◽

Finite Element Software ◽

Straight Line ◽

Large Width ◽

Angle Steel

The dissertation taked the ZBS2 straight-line tower in the UHV line project as the object,used the finite element software ANSYS to establish finite element model and did a analysis about its dynamic characteristics. Considering width and thickness of large width angle steel,the section area of large width angle steel is larger than normal angle steel,and the application of large width angle steel can increase bearing capacity of the member.Therefore,this article taked large width angle steel to replace double combined angle steels in the main members of the tower,and calculated the ultimate bearing capacity. Analysis of comparison indicate that the ultimate bearing capacity increases by 13% when large width angle steel is used.Therefore it is feasible and advantageous that large width angle steel uses in the UHV transimission tower,and it provide a reference and basis for future design of the UHV transmission tower with large width angle steel.

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Effect of Unbalanced Force Loading on the Safety of Transmission Tower

IOP Conference Series Earth and Environmental Science ◽

10.1088/1755-1315/898/1/012011 ◽

2021 ◽

Vol 898 (1) ◽

pp. 012011

Author(s):

Hongji Zhang

Keyword(s):

Transmission Lines ◽

Simulation Analysis ◽

Practical Importance ◽

Element Model ◽

Transmission Tower ◽

Maximum Displacement ◽

Force Loading ◽

Finite Element Software ◽

Unbalanced Force ◽

Transmission Towers

Abstract High-voltage transmission towers, as support points for overhead transmission lines, are often under the condition of unbalanced force loading. Transmission towers can collapse because of the unbalanced forces, leading to the power outage. Therefore, it is of practical importance to set a research on the effect of unbalanced force loading on the safety of transmission tower. In this paper, based on the prototype of 500kV transmission tower, the integral beam element model is established by ABAQUS finite element software for simulation analysis. Static load mode and unbalanced force loading were considered in this simulation model. Through the comparative analysis of the maximum displacement and stress in transmission tower, the safety of the 500kV transmission tower was analyzed. The variations of maximum displacement and Mises stress with the increasing unbalanced force were obtained. The limit of unbalanced force the 500kV transmission tower can sustain was given by comparing the simulated results.

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Effects of Different Initial Imperfections including Residual Stress on the Compressive Bearing Capacity of Steel Angles in Towers

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.252.167 ◽

2012 ◽

Vol 252 ◽

pp. 167-171

Author(s):

Bin Rong Zhu ◽

Jing Bo Yang ◽

Qing Hua Li

Keyword(s):

Residual Stress ◽

Bearing Capacity ◽

Slenderness Ratio ◽

Shell Element ◽

General Purpose ◽

Transmission Tower ◽

Initial Imperfections ◽

Finite Element Software ◽

Steel Angles ◽

The Impact

Angles are extensively used in latticed transmission tower. Initial imperfections have a significant impact on the compressive instability and failure of angle components. To study the impact of different initial imperfections on the compressive bearing capacity, general-purpose finite element software ANSYS is used. With shell element SHELL181, selecting angle L200×20 of the slenderness ratio of 20, 40, 60, 80, 100 and 120, the bearing performance analysis with initial imperfections is conducted, including initial bending, section defects, initial eccentricity, residual stress, and a combination of imperfections. At the same time, for the angle components of the optimal slenderness ratio of 40 and slenderness ratio of 80, under the single influence of initial bending, section defects and residual stress, how the size of the value of the imperfections affects the bearing performance is investigated.

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Energy Dissipation Capacity of Friction-Type Reinforcing Members Installed at a Transmission Tower

Smart Materials, Adaptive Structures and Intelligent Systems, Volume 2 ◽

10.1115/smasis2008-492 ◽

2008 ◽

Author(s):

Ji-Hun Park ◽

Byoung-Wook Moon ◽

Sung-Kyung Lee ◽

Kyung-Won Min

Keyword(s):

Energy Dissipation ◽

Local Deformation ◽

Test Results ◽

Transmission Tower ◽

Transmission Towers ◽

Tower Structure ◽

Loading Tests ◽

Energy Dissipation Capacity ◽

Reliable Design ◽

Cyclic Loading Tests

Friction-type reinforcing members (FRMs) developed for the purpose of enhancing the wind-resistant performance of transmission towers are tested experimentally. The FRMs, in the middle of which slotted bolted connections (SBCs) are installed, are placed on the outside of tower legs, and provide additional damping and stiffness to the tower structure under bending deformations. Firstly, the SBCs used in the FRMs are tested for various frictional sliding interface conditions. Secondly, the FRMs are installed on a 1/2 scale plane tower substructure and cyclic loading tests are conducted. Energy dissipation capacity and effects from local deformations of the FRMs and joint slips are investigated. From the test results, remarkable energy dissipation capacity, reaching to the 2.4 times of that before the installation of the FRMs, is observed. However, the local deformation of the SBC and joint slip should be prevented for more reliable design of the FRMs.

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Enhancing the power generation of Rhodopseudomonas palustris-based MFC

International Journal of Applied Electromagnetics and Mechanics ◽

10.3233/jae-209444 ◽

2020 ◽

Vol 64 (1-4) ◽

pp. 1261-1268

Author(s):

Shu Otani ◽

Dang-Trang Nguyen ◽

Kozo Taguchi

Keyword(s):

Activated Carbon ◽

Rhodopseudomonas Palustris ◽

Ozone Treatment ◽

Maximum Power Density ◽

On Demand ◽

Long Time ◽

Dry Conditions ◽

Carbon Sheet ◽

Uv Ozone

In this study, a portable and disposable paper-based microbial fuel cell (MFC) was fabricated. The MFC was powered by Rhodopseudomonas palustris bacteria (R. palustris). An activated carbon sheet-based anode pre-loaded organic matter (starch) and R. palustris was used. By using starch in the anode, R. palustris-loaded on the anode could be preserved for a long time in dry conditions. The MFC could generate electricity on-demand activated by adding water to the anode. The activated carbon sheet anode was treated by UV-ozone treatment to remove impurities and to improve its hydrophilicity before being loaded with R. palustris. The developed MFC could generate the maximum power density of 0.9 μW/cm2 and could be preserved for long-term usage with little performance degradation (10% after four weeks).

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