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Dynamic Responses of Long-Span Transmission Tower-Line System Subjected to Broken Wires
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作者 夏正春 李黎 +1 位作者 方秦汉 龙晓鸿 《Journal of Southwest Jiaotong University(English Edition)》 2008年第4期309-319,共11页
A macroscopic finite element modeling approach was proposed to calculate the vibration of a tower-line system subjected to broken wires with software ANSYS/LS-DYNA. In the finite element model, not only the nonlineari... A macroscopic finite element modeling approach was proposed to calculate the vibration of a tower-line system subjected to broken wires with software ANSYS/LS-DYNA. In the finite element model, not only the nonlinearity of wires and suspension insulators are considered, but also the support towers are included. The incremental and iterative approaches are combined by applying the unbalanced loads incrementally during each iteration cycle. The approach was illustrated with an example of a Hanjiang- River long-span transmission line system subjected to a shield wire and a conductor failure, respectively. The analysis results showed that the proposed dynamic simulation approach can demonstrate the kinetic process of the tower-line system subjected to wire ruptures: The frequencies of line components were lower and densely distributed, but the frequencies of tower components were higher and sparsely distributed. Anyhow, the dynamic effects of wire ruptures on tower-line system could not be ignored in analysis of tower-line system subjected wire failures. 展开更多
关键词 Electric transmission tower-line coupling Wire rupture Dynamic responses ANSYS/LS-DYNA
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Research on Transmission Line Tower Tilting and Foundation State Monitoring Technology Based onMulti-Sensor Cooperative Detection and Correction
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作者 Guangxin Zhang Minghui Liu +4 位作者 Shichao Cheng Minzhen Wang Changshun Zhao Hongdan Zhao Gaiming Zhong 《Energy Engineering》 EI 2024年第1期169-185,共17页
The transmission line tower will be affected by bad weather and artificial subsidence caused by the foundation and other factors in the power transmission.The tower’s tilt and severe deformation will cause the buildi... The transmission line tower will be affected by bad weather and artificial subsidence caused by the foundation and other factors in the power transmission.The tower’s tilt and severe deformation will cause the building to collapse.Many small changes caused the tower’s collapse,but the early staff often could not intuitively notice the changes in the tower’s state.In the current tower online monitoring system,terminal equipment often needs to replace batteries frequently due to premature exhaustion of power.According to the need for real-time measurement of power line tower,this research designed a real-time monitoring device monitoring the transmission tower attitude tilting and foundation state based on the inertial sensor,the acceleration of 3 axis inertial sensor and angular velocity raw data to pole average filtering pre-processing,and then through the complementary filtering algorithm for comprehensive calculation of tilt angle,the system meets the demand for inclined online monitoring of power line poles and towers regarding measurement accuracy,with low cost and power consumption.The optimization multi-sensor cooperative detection and correction measured tilt angle result relative accuracy can reach 1.03%,which has specific promotion and application value since the system has the advantages of unattended and efficient calculation. 展开更多
关键词 transmission line tower tilting MULTI-SENSOR foundation state monitoring collaborative detection
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Wind-induced vibration control of long-span power transmission towers 被引量:1
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作者 尹鹏 《Journal of Chongqing University》 CAS 2009年第2期112-124,共13页
We investigated wind-induced vibration control of long-span power transmission towers based on a case study of the Jingdongnan-Nanyang-Jingmen 1 000 kV transmission line project in P. R. China. The height of the cup t... We investigated wind-induced vibration control of long-span power transmission towers based on a case study of the Jingdongnan-Nanyang-Jingmen 1 000 kV transmission line project in P. R. China. The height of the cup tower is 181 m with a ground elevation of 47 m, which makes it a super flexible and wind-sensitive structure. Therefore, we should analyze the wind- resistant capacity of the system. We simulated applicable transverse fluctuating wind velocity field, developed a lead-rubber damper (LRD) for controlling wind-induced vibration of long-span transmission towers, deduced LRD calculation model parameter, and researched the best layout scheme and installation method of LRD. To calculate the wind-induced response of tower-line coupling system in seven layout schemes, we used the time history analysis method, and obtained the efficiencies of wind-induced vibration control. LRD deformation research proved that the damp of all LRDs was efficient under the designed wind velocity when they were laid along the edge of tower heads. We studied the controlling efficiency resulting fTom only applying stiffness to the tower polos where the dampers used to be laid under the designed wind velocity. The results show that the controlling efficiency was not ideal when the stiffness is increased on the poles only. Therefore, LRD should conlxibute to both the stiffness and damp of a structure to effectively reduce the dynamic response of a tower-line coupling system under strong winds. We also discussed the controlling efficiency of LRD under static winds. The results show that there was little difference between displacements derived by the finite clement time history method and those obtained by static wind method conducted by a design institute. This means the simulation on space relevant wind velocity field was accurate and reasonable. 展开更多
关键词 transmission towers lead-rubber damper wind-induced vibration control
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The changing process and trend of ground temperature around tower foundations of Qinghai-Tibet Power Transmission line 被引量:3
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作者 YanLi Xie QiHao Yu +2 位作者 YanHui You ZhongQiu Zhang TingTao Gou 《Research in Cold and Arid Regions》 CSCD 2019年第1期13-20,共8页
After the construction of Qinghai-Tibet Highway and Railway, the Qinghai-Tibet Power Transmission(QTPT) line is another major permafrost engineering project with new types of engineering structures. The changing proce... After the construction of Qinghai-Tibet Highway and Railway, the Qinghai-Tibet Power Transmission(QTPT) line is another major permafrost engineering project with new types of engineering structures. The changing process and trend of ground temperature around tower foundations are crucial for the stability of QTPT. We analyzed the change characteristics and tendencies of the ground temperature based on field monitoring data from 2010 to 2014. The results reveal that soil around the tower foundations froze and connected with the artificial permafrost induced during the construction of footings after the first freezing period, and the soil below the original permafrost table kept freezing in subsequent thawing periods. The ground temperature lowered to that of natural fields, fast or slowly for tower foundations with thermosyphons,while for tower foundations without thermosyphons, the increase in ground temperature resulted in higher temperature than that of natural fields. Also, the permafrost temperature and ice content are significant factors that influence the ground temperature around tower foundations. Specifically, the ground temperature around tower foundations in warm and ice-rich permafrost regions decreased slowly, while that in cold and ice poor permafrost regions cooled faster. Moreover, foundations types impacted the ground temperature, which consisted of different technical processes during construction and variant of tower footing structures. The revealed changing process and trend of the ground temperature is beneficial for evaluating the thermal regime evolution around tower foundations in the context of climate change. 展开更多
关键词 Qinghai-Tibet Power transmission line tower FOUNDATION ground temperature change CHARACTERISTIC TREND
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A new framework for evaluating along-wind responses of a transmission tower 被引量:3
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作者 Liu Guohuan and Li Hongnan School of Civil and Hydraulic Engineering, Dalian University of Technology, Dalian 116023, China PhD Professor 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2009年第1期87-93,共7页
In this paper, an analytical framework to evaluate the along-wind-induced dynamic responses of a transmission tower is presented. Two analytical models and a new method are developed: (1) a higher mode generalized ... In this paper, an analytical framework to evaluate the along-wind-induced dynamic responses of a transmission tower is presented. Two analytical models and a new method are developed: (1) a higher mode generalized force spectrum (GFS) model of the transmission tower is deduced; (2) an analytical model that includes the contributions of the higher modes is further derived as a rational algebraic formula to estimate the structural displacement response; and (3) a new approach, applying load with displacement (ALD) instead of force, to solve the internal force of transmission tower is given. Unlike conventional methods, the ALD method can avoid calculating equivalent static wind loads (ESWLs). Finally, a transmission tower structure is used as a numerical example to verify the feasibility and accuracy of the ALD method. 展开更多
关键词 along-wind-induced dynamic responses transmission tower generalized force spectrum equivalent static wind loads
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Limits to foundation displacement of an extra high voltage transmission tower in a mining subsidence area 被引量:10
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作者 Shu Qianjin Yuan Guanglin +1 位作者 Guo Guangli Zhang Yunfeit 《International Journal of Mining Science and Technology》 2012年第1期13-18,共6页
Given the background of a transmission tower erected on a particular mining subsidence area,we used finite element modeling to analyze the anti-deformation performance of transmission towers under a number of differen... Given the background of a transmission tower erected on a particular mining subsidence area,we used finite element modeling to analyze the anti-deformation performance of transmission towers under a number of different load conditions,including horizontal foundation displacement,uneven vertical downward displacement,wind loads and icing conditions.The results show that the failure in stability of a single steel angle iron represents the limit of the tower given ground deformation.We calculated the corresponding limits of foundation displacements.The results indicate that compression displacement of the foundation is more dangerous than tension displacement.Under complex foundation displacement conditions,horizontal foundation displacement is a key factor leading to failure in the stability of towers.Under conditions of compression or tension displacement of the foundation,wind load becomes the key factor.Towers do not fail when foundation displacements are smaller than 1% (under tension) or 0.5% (under horizontal compression or single foundation subsidence) of the distance between two supports. 展开更多
关键词 Mining subsidence area Electricity transmission tower Foundation displacement limit Finite element analysis Limit state Stability failure
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Model experiment on anti-deformation performance of a self-supporting transmission tower in a subsidence area 被引量:3
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作者 Yuan Guanglin Shu Qianjin +3 位作者 Zhang Yunfei Liu Tao Ji Yongsheng Xu Guoan 《International Journal of Mining Science and Technology》 2012年第1期57-61,共5页
A large number of high-voltage power transmission towers have recently been constructed in mining areas prone to subsidence. In order to ensure the safety of the transmission towers and the safe operation of transmiss... A large number of high-voltage power transmission towers have recently been constructed in mining areas prone to subsidence. In order to ensure the safety of the transmission towers and the safe operation of transmission systems, it is imperative to carry out research on the anti-deformation performance of transmission towers. In our study, we performed experiments on the anti-deformation performance of a transmission tower in a subsidence area on a scale model with a geometric scale ratio of 1:5 and analyzed the failure mechanism of the tower members. The results show that, when the axial distance between two supports changes, destabilization failure most likely occurs in the members of the bottom transverse layer because some parts of the main diagonal member bars yield under the action of compression. The failure mechanism of the tower members basically coincides with the lever principle. 展开更多
关键词 Subsidence area transmission tower Anti-deformation performance Similar model EXPERIMENT
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Some Advances in the Application of Weathering and Cold-Formed Steel in Transmission Tower 被引量:2
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作者 Fengli Yang Junke Han +1 位作者 Jingbo Yang Zheng Li 《Journal of Electromagnetic Analysis and Applications》 2009年第1期24-30,共7页
Application of weathering and cold-formed steel in transmission lines can reduce steel consumption and environmental pollution. Some advances in the studies on the weathering and cold-formed steel in transmission towe... Application of weathering and cold-formed steel in transmission lines can reduce steel consumption and environmental pollution. Some advances in the studies on the weathering and cold-formed steel in transmission tower are introduced. Firstly, corrosion-resistant tests of weathering steel samples under different simulating technical atmospheres were carried out separately for 240 hours. It shows that the corrosion degree of joint samples is higher than that of single chip samples, and the corrosion-resistant performance of weathering steel is superior to common carbon steel. The corrosion-resistance of weathering steel meets with the requirement of transmission tower. Secondly, experiments and finite element analysis for cold-formed angles and a 220kV prototype tower were completed, and the stability coeffi-cient fitting curves as well as the modification formulas of slenderness ratio for cold-formed members were determined. According to the structural characteristics of transmission towers, four sections of cold-formed angles with different sections and slenderness ratios were selected in this study. The finite element model well predicted the buckling behav-iour of the cold-formed members. Ultimate loads calculating by the fitting curve were well agreed to the experimental values, especially for the members with small slenderness ratios. Weight of the cold-formed steel tower can be reduced by more than 5 percent after considering the strength enhancement. Cost of the weathering and cold-formed steel transmission tower is nearly equivalent to that of hot-rolled steel tower with hot galvanizing. 展开更多
关键词 WEATHERING STEEL COLD-FORMED STEEL BOLTED Joint Corrosion-Resistant TEST Prototype TEST Buckling Analysis transmission tower
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Study on Improvement of Seismic Performance of Transmission Tower Using Viscous Damper 被引量:3
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作者 Masayuki Matsumoto Akira Kasai +2 位作者 Taiji Mazda Nobuyuki Ishida Yuki Ito 《Journal of Civil Engineering and Architecture》 2017年第5期455-467,共13页
The earthquake resistance of transmission tower has been often discussed from the viewpoint of reinforcing the foundation of steel tower, but there are also few studies considering the damping characteristics of the t... The earthquake resistance of transmission tower has been often discussed from the viewpoint of reinforcing the foundation of steel tower, but there are also few studies considering the damping characteristics of the tower. This paper focuses on the viscous damper which has been adopted for seismic reinforcement of bridges in recent years. The purpose of this study is to improve the seismic performance of steel tower by giving the high damping to the tower. We construct a single tower model considering the influence of transmission line, and then simulate the vibration characteristics and seismic behavior of the tower by the eigenvalue analysis and the dynamic response analysis. The results show that the transmission tower with viscous damper can reduce its own response effectively and drastically. This research concludes that it is necessary to consider the extreme increase of steel tower's response depending on the seismic wave and the collapse of steel tower can be avoided by using the optimum damper in the design of the transmission tower. 展开更多
关键词 Dynamic analysis EARTHQUAKE response reduction seismic damper transmission tower.
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Application of Lead Viscoelastic Dampers to Wind Vibration Control on Big-Span Power Transmission Tower 被引量:1
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作者 梁政平 李黎 +1 位作者 尹鹏 段松涛 《Journal of Southwest Jiaotong University(English Edition)》 2008年第4期320-328,共9页
To study the wind vibration response of power transmission tower, the lead viscoelastic dampers (LVDs) were applied to a cup tower. With time history analysis method, the displacement, velocity, acceleration and for... To study the wind vibration response of power transmission tower, the lead viscoelastic dampers (LVDs) were applied to a cup tower. With time history analysis method, the displacement, velocity, acceleration and force response of the tower was calculated and analyzed. The results show that the control effect of lead viscoelastic dampers is very good, and the damping ratio can reach 20% or more when they are applied to the tower head. 展开更多
关键词 transmission tower Lead viscoelastic damper Wind-induced vibration control
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Process Analysis of Double Circuit Transmission Line Trip-out on the Same Tower Due to Lightning
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作者 DUAN Da-peng REN Zhi-gang WANG Peng YE Kuan CHANG Xiao-qi LI Wei 《高压电器》 CAS CSCD 北大核心 2011年第9期31-36,43,共7页
In recent years,several failures of double circuit transmission line on the same tower due to lightning were happened in Beijing power grid.Although it can be reclosed successful,the lightning strike caused a grave th... In recent years,several failures of double circuit transmission line on the same tower due to lightning were happened in Beijing power grid.Although it can be reclosed successful,the lightning strike caused a grave threat to the power grid security.The cause of the accident and the accident process were studied for the sake of further understanding of the impact of lightning on power grid.As an example,110 kV double circuit transmission line(Xilong-line) was analyzed.At first,the system topology was given.Through the analysis on relay protection actions and the fault recorder data,over voltage on the insulator strings was calculated.Based on the analysis and the calculation,accident cause and the process were presented respectively.Secondly,it comes to the conclusion that the lightning failure was caused by counterattack.The wave of the lightning over voltage would spread to the not grounded neutral point of the transformers,and make the neutral protective gap breakdown,then cause freewheeling with the frequency of 50 Hz.As results of the relay protection,the double circuit transmission line all tripped out.Finally,the causes of the accident were proposed that included terrain features,large corner towers,strong thunderstorm weather and poor grounded contact of the tower. 展开更多
关键词 double circuit transmission lines on the same tower lightning trip-out at the same time fault recorder over-voltage calculation lightning protection
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Evaluating transmission towers potentials during ground faults
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作者 Maria VINTAN 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2008年第2期182-189,共8页
During ground faults on transmission lines,a number of towers near the fault are likely to acquire high potentials to ground.These tower voltages,if excessive,may present a hazard to humans and animals.This paper pres... During ground faults on transmission lines,a number of towers near the fault are likely to acquire high potentials to ground.These tower voltages,if excessive,may present a hazard to humans and animals.This paper presents analytical methods in order to determine the transmission towers potentials during ground faults,for long and short lines.The author developed a global systematic approach to calculate these voltages,which are dependent of a number of factors.Some of the most important factors are:magnitudes of fault currents,fault location with respect to the line terminals,conductor arrangement on the tower and the location of the faulted phase,the ground resistance of the faulted tower,soil resistivity,number,material and size of ground wires.The effects of these factors on the faulted tower voltages have been also examined for different types of power lines. 展开更多
关键词 Overhead transmission lines Ground fault tower potential
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Elastic Dynamic Stability of Big-Span Power Transmission Tower Subjected to Seismic Excitations
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作者 张行 李黎 +1 位作者 方秦汉 叶昆 《Journal of Southwest Jiaotong University(English Edition)》 2009年第1期65-71,共7页
By combining the time-history response analysis and the eigenvalue buckling analysis, this paper developed a computational procedure to study the elastic dynamic stability of a transmission tower by APDL language in A... By combining the time-history response analysis and the eigenvalue buckling analysis, this paper developed a computational procedure to study the elastic dynamic stability of a transmission tower by APDL language in ANSYS. The influences of different input directions of seismic excitations and damping ratio on the elastic dynamic stability of tower were discussed. The following conclusions were obtained: ( 1 ) Longitudinal direction of the transmission lines is the worst input direction of seismic excitation for the transmission tower. (2) Dead load has no significant effect on the critical load and the occurrence time of buckling. (3) Vertical input of seismic excitations has no great effect on the dynamic stability of the transmission tower. (4) Damping effect has an influence on the dynamic stability of the transmission tower; however, the inherent characteristics of dynamic buckling is not changed. 展开更多
关键词 transmission tower Seismic excitation Elastic dynamic stability Big span
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The Integrated System of Aerial Photogrammetry and Tower Locations Optimization for Transmission Lines
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作者 Xie Yuan, Pan Yijun, Fu Bin Northwest Power Design Institute 《Electricity》 1996年第4期45-48,共4页
This paper describes the functions and the features of the integrated system of aerial survey and tower locations optimization for transmission lines, which includes all stages from data acquisition, data transmission... This paper describes the functions and the features of the integrated system of aerial survey and tower locations optimization for transmission lines, which includes all stages from data acquisition, data transmission and data processing to automatic optimization of the tower locations and drawing. The paper also briefly describes the economic benefit gained from this system, and finally proposes the directions of the future development for this system. 展开更多
关键词 PRO The Integrated System of Aerial Photogrammetry and tower Locations Optimization for transmission Lines
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Dynamic Analysis of Overhead Transmission Lines under Turbulent Wind Loading 被引量:2
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作者 Alok Dua Mathias Clobes +1 位作者 Thomas Hobbel Vasant Matsagar 《Open Journal of Civil Engineering》 2015年第4期359-371,共13页
Transmission tower-line systems are designed using static loads specified in various codes. This paper compares the dynamic response of a test transmission line with the response due to static loads given by Eurocode.... Transmission tower-line systems are designed using static loads specified in various codes. This paper compares the dynamic response of a test transmission line with the response due to static loads given by Eurocode. Finite element design software SAP2000 was used to model the towers and lines. Non-linear dynamic analysis including the large displacement effects was carried out. Macroscopic aspects of wind coherence along element length and integration time step were investigated. An approach is presented to compare the probabilistic dynamic response due to 7 different stochastically simulated wind fields with the response according to EN-50341. The developed model will be used to study the response recorded on a test line due to the actual wind speed time history recorded. It was found that static load from EN overestimated the strength of conductor cables. The response of coupled system considering towers and cables was found to be different from response of only cables with fixed supports. 展开更多
关键词 Dynamic Analysis Finite Element Method SAP2000 transmission towers transmission Lines
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GFRP布无损加固输电铁塔角钢受力性能研究 被引量:1
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作者 王彦海 李书炀 +2 位作者 邓德慧 尹恒伟 吴德强 《广西大学学报(自然科学版)》 CAS 北大核心 2024年第1期24-36,共13页
针对现役输电铁塔在覆冰、风荷载、边坡变形等作用下可能存在承载力不足的问题,研究玻璃纤维增强复合材料(GFRP)布无损加固铁塔角钢的受力性能。首先,利用文献中的物理试验对加固钢材数值试验方法进行验证;其次,以铁塔角钢为研究对象,... 针对现役输电铁塔在覆冰、风荷载、边坡变形等作用下可能存在承载力不足的问题,研究玻璃纤维增强复合材料(GFRP)布无损加固铁塔角钢的受力性能。首先,利用文献中的物理试验对加固钢材数值试验方法进行验证;其次,以铁塔角钢为研究对象,基于验证的数值试验方法建立72组有限元分析模型,探讨长细比、GFRP布粘贴层数、粘贴长度等因素对角钢极限承载力的影响;最后,推导并改进GFRP布角钢复合构件理论承载力计算方法。结果表明:不同长细比对构件极限承载力影响较大,当角钢长细比大于70时,加固后的承载力提升不明显;增加GFRP布粘贴层数,角钢承载力大幅提升,粘贴8层GFRP布的承载力提升率最高达41.03%;柱中GFRP布粘贴长度为75%与粘贴长度为100%的角钢极限承载力相比提升不大,仅为0.27%~2.10%;对推导的GFRP布角钢复合构件理论承载力计算方法引入修正系数后,数值试验与理论计算值相对误差缩小至-2.70%~1.77%,有效提升理论解计算精度。在对现役铁塔加固时,只需对角钢全长的75%粘贴6~8层GFRP布进行加固,且对于长细比λ≤70的角钢加固效果更好。 展开更多
关键词 输电铁塔 复合材料 钢结构无损加固 极限承载力 修正系数
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钢管输电塔挂线节点足尺模型失效模式与承载力提升分析
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作者 翟彬 李素超 +3 位作者 张丽娟 徐再根 王志远 毛晨曦 《地震研究》 CSCD 北大核心 2024年第1期1-9,共9页
针对特高压钢管输电塔挂线位置节点在极端荷载下的安全性,提出了挂线节点双侧挂线板协同受力的构造改进措施,并对比研究两种挂线节点的极限承载力与失效模式。通过足尺挂线节点处的承载力试验与有限元分析,比较挂线节点在单侧板受力、... 针对特高压钢管输电塔挂线位置节点在极端荷载下的安全性,提出了挂线节点双侧挂线板协同受力的构造改进措施,并对比研究两种挂线节点的极限承载力与失效模式。通过足尺挂线节点处的承载力试验与有限元分析,比较挂线节点在单侧板受力、双侧板受力情况下的应力分布与承载能力,分析传力螺母与挂线板之间的合理初始间距。结果表明:双侧受力时两侧挂线板均发生弯曲破坏,受力形式更加合理,节点板应力分布更加均匀,挂线点的屈服承载力可以提升一倍以上,传力螺母与挂线板之间的合理初始间隙为2~4 mm。 展开更多
关键词 特高压输电塔 挂线节点 承载力 足尺试验 有限元模拟 传力螺母
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新型圆筒式电涡流阻尼器性能优化及试验研究
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作者 姜岚 皮柯洋 +1 位作者 程若恒 唐波 《机械设计与制造》 北大核心 2024年第9期350-355,共6页
为了有效抑制输电铁塔钢管构件的涡激振动问题,设计了一种基于电涡流原理被动抑制的新型径向充磁圆筒式电涡流阻尼器。首先,提出了四种磁路的设计方案,分析了静态磁场的气隙密度分布,并采用瞬态分析方法,讨论了不同方案对阻尼器阻尼系... 为了有效抑制输电铁塔钢管构件的涡激振动问题,设计了一种基于电涡流原理被动抑制的新型径向充磁圆筒式电涡流阻尼器。首先,提出了四种磁路的设计方案,分析了静态磁场的气隙密度分布,并采用瞬态分析方法,讨论了不同方案对阻尼器阻尼系数的影响;最后提出了四种导体的设计构型,并对导体构型进行优化。针对最优构型的阻尼器,搭建了新型径向充磁圆筒式电涡流阻尼器在简谐载荷激励下的试验模型,通过试验与仿真的对比,验证了仿真结果的可靠性,且随着振动频率的增大,阻尼系数有减小的趋势。以期新型径向充磁圆筒式电涡流阻尼器能为输电钢管塔涡激减振提供初步参考。 展开更多
关键词 输电钢管塔 涡激振动 电磁阻尼器 阻尼系数
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格构式钢管输电塔架的体型系数和雷诺数效应
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作者 沈国辉 李懿鹏 +2 位作者 赵英能 韩康辉 郭勇 《湖南大学学报(自然科学版)》 EI CAS CSCD 北大核心 2024年第3期31-38,共8页
采用天平测力风洞试验获得亚临界范围钢管塔架的体型系数,研究塔架体型系数随密实度的变化特征,基于规范数据拟合体型系数从亚临界到超临界条件下的雷诺数折算系数,基于试验结果开展塔架体型系数与规范值的对比.试验结果表明,相同密实... 采用天平测力风洞试验获得亚临界范围钢管塔架的体型系数,研究塔架体型系数随密实度的变化特征,基于规范数据拟合体型系数从亚临界到超临界条件下的雷诺数折算系数,基于试验结果开展塔架体型系数与规范值的对比.试验结果表明,相同密实度下横担的体型系数大于塔身,其原因为横担杆件长细比以及杆件前后的等效间距比均较大;在亚临界条件下塔身体型系数试验值与JEC-TR-00007—2015、DL/T 5551—2018和GB 50009—2012规范值接近,而横担体型系数大于各国规范值;亚临界和超临界条件下各国规范的钢管塔架体型系数随着密实度ϕ的增加而降低,使用最小二乘法拟合获得雷诺数折算系数为0.63+0.72ϕ;在超临界条件下,塔身的体型系数与DL/T 5551—2018、GB 50009—2012规范结果接近,横担的体型系数与IEC 60826—2017和ASCE MOP 74—2020规范结果接近. 展开更多
关键词 输电塔 钢管塔架 体型系数 测力天平 雷诺数
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盐渍土环境下考虑耐久性损伤的输电塔风振时程分析
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作者 梁岩 赵付林 +1 位作者 冯浩琪 刘昌海 《建筑结构》 北大核心 2024年第8期74-84,共11页
长期服役于盐渍土环境下的输电塔耐久性损伤较为严重,当其材料力学性能退化到一定程度时,在强风作用下,输电塔可能会发生破坏,危害线路的安全运行。基于±800kV天中线特高压直流输电工程直线塔,考虑基础钢筋锈蚀、基础混凝土侵蚀、... 长期服役于盐渍土环境下的输电塔耐久性损伤较为严重,当其材料力学性能退化到一定程度时,在强风作用下,输电塔可能会发生破坏,危害线路的安全运行。基于±800kV天中线特高压直流输电工程直线塔,考虑基础钢筋锈蚀、基础混凝土侵蚀、输电塔杆塔钢材锈蚀以及基础箍筋的约束效应,在ABAQUS有限元软件中建立塔-线-基础耦合模型,研究不同风攻角和材料耐久性损伤对塔身动力响应的影响。结果表明:90°风攻角下塔身顺风向位移最大,为最不利风向基本工况;90°风攻角下输电塔塔顶顺风向位移响应贡献主要以背景分量为主,但共振分量也有一定贡献,主要以输电塔1阶振型频率为主,且随着服役时间的增加,振型频率逐渐降低,相应响应的贡献程度逐渐提高;相同风荷载作用下,随着服役时间的增加,塔身位移逐渐增大,相同服役时间下,随着塔身高度的增加,塔身位移响应峰值增长速度变快,结构振动更加明显,材料耐久性损伤对输电塔的位移响应影响较大。 展开更多
关键词 输电塔 耐久性 风攻角 谐波叠加法 时程分析
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