Transmission tower-line systems(TTLSs)play a crucial role in the long-distance transmission of electrical energy,often necessitating their crossing through active fault areas.However,previous studies have given limite...Transmission tower-line systems(TTLSs)play a crucial role in the long-distance transmission of electrical energy,often necessitating their crossing through active fault areas.However,previous studies have given limited attention to the seismic performance of fault-crossing transmission TTLSs,particularly in terms of considering the impact of permanent ground motion displacements(PGMDs).This study attempts to address this concern by evaluating the seismic performance of TTLSs exposed to fault earthquakes.Three strike-slip ground motions are carefully selected,and the corresponding PGMDs are accurately replicated through baseline adjustment.A meticulously designed and fabricated reduced-scale experimental model of a TTLS is then employed to investigate the influence of the fault crossing location(FCL)on its seismic performance.The shake table tests conducted unequivocally demonstrate that PGMDs significantly amplify the seismic responses of the TTLS and identify the most unfavorable FCL.Furthermore,a finite element model(FEM)is developed and its accuracy is validated by comparing it with the experimental results.Parametric analyses are conducted to explore the effects of fault crossing angles(FCAs)and PGMD amplitudes on the seismic performances of TTLSs.This study is expected to contribute valuable insights for the seismic design and performance analysis of TTLSs crossing fault areas.展开更多
Collapses of transmission towers were often observed in previous large earthquakes such as the Chi-Chi earthquake in Taiwan and Wenchuan earthquake in Sichuan,China. These collapses were partially caused by the pullin...Collapses of transmission towers were often observed in previous large earthquakes such as the Chi-Chi earthquake in Taiwan and Wenchuan earthquake in Sichuan,China. These collapses were partially caused by the pulling forces from the transmission lines generated from out-of-phase responses of the adjacent towers owing to spatially varying earthquake ground motions. In this paper,a 3D finite element model of the transmission tower-line system is established considering the geometric nonlinearity of transmission lines. The nonlinear responses of the structural system at a canyon site are analyzed subjected to spatially varying ground motions. The spatial variations of ground motion associated with the wave passage,coherency loss,and local site effects are given. The spatially varying ground motions are simulated stochastically based on an empirical coherency loss function and a filtered Tajimi-Kanai power spectral density function. The site effect is considered by a transfer function derived from 1D wave propagation theory. Compared with structural responses calculated using the uniform ground motion and delayed excitations,numerical results indicate that seismic responses of transmission towers and power lines are amplified when considering spatially varying ground motions including site effects. Each factor of ground motion spatial variations has a significant effect on the seismic response of the structure,especially for the local site effect. Therefore,neglecting the earthquake ground motion spatial variations may lead to a substantial underestimation of the response of transmission tower-line system during strong earthquakes. Each effect of ground motion spatial variations should be incorporated in seismic analysis of the structural system.展开更多
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
风雨载荷对输电塔线体系的安全性有着重要影响.本文对某110kV输电线路中塔线耦联体系在风雨载荷作用下的动力特性进行分析.首先,在Ansys软件中建立某110 k V输电塔线体系有限元模型,并进行模态分析.其次,结合Davenport风速谱与雨载荷相...风雨载荷对输电塔线体系的安全性有着重要影响.本文对某110kV输电线路中塔线耦联体系在风雨载荷作用下的动力特性进行分析.首先,在Ansys软件中建立某110 k V输电塔线体系有限元模型,并进行模态分析.其次,结合Davenport风速谱与雨载荷相关理论,在Matlab中生成与加载节点对应的风雨耦合载荷.最后,研究在此耦合载荷下的塔线体系的动力响应,并探究在不同风向角和有无雨载荷的情况下其动力响应的结果.结果显示:导地线在整体上增加了塔线体系刚度,但由于其自身在横线方向具有较强“舞动效应”,导致其在横线方向和顺线方向耦联效应有所不同;90°风向角为塔线体系最不利风向角,此时塔线体系动力响应达到最大值;在降雨量为20mm/h的情况下,计及雨载荷将增加塔线体系动力响应范围约为5%~10%,雨载荷对单塔的作用几乎可以忽略不计,其主要是通过加剧导地线的“舞动效应”,进而增加塔线体系的动力响应.展开更多
架空输电线路设计过程中,人工计算塔腿坐标与占地范围的shapefile(SHP)文件成图效率低、错误率高。针对这一问题,提出一种基于开源地理信息系统(geographic information system,GIS)库的自动化绘图方法,该方法不仅建立塔腿坐标计算的几...架空输电线路设计过程中,人工计算塔腿坐标与占地范围的shapefile(SHP)文件成图效率低、错误率高。针对这一问题,提出一种基于开源地理信息系统(geographic information system,GIS)库的自动化绘图方法,该方法不仅建立塔腿坐标计算的几何模型,还利用地理空间数据抽象库(geospatial data abstraction library,GDAL)/矢量数据处理库(OpenGIS Simple Features Reference Implementation,OGR)实现从杆塔参数到占地范围SHP文件的批量生成与可视化。西藏某500 kV线路工程的应用表明:该方法计算的塔腿坐标中误差为0.2 mm,实现了全流程、自动化塔位绘图,大幅提升了工作效率与数据准确性,而且软件安装便捷,具有良好的推广应用价值。展开更多
基金Shandong Provincial Natural Science Foundation for Distinguished Young Scholars under Grant No.ZR2022JQ27the Taishan Scholars Program
文摘Transmission tower-line systems(TTLSs)play a crucial role in the long-distance transmission of electrical energy,often necessitating their crossing through active fault areas.However,previous studies have given limited attention to the seismic performance of fault-crossing transmission TTLSs,particularly in terms of considering the impact of permanent ground motion displacements(PGMDs).This study attempts to address this concern by evaluating the seismic performance of TTLSs exposed to fault earthquakes.Three strike-slip ground motions are carefully selected,and the corresponding PGMDs are accurately replicated through baseline adjustment.A meticulously designed and fabricated reduced-scale experimental model of a TTLS is then employed to investigate the influence of the fault crossing location(FCL)on its seismic performance.The shake table tests conducted unequivocally demonstrate that PGMDs significantly amplify the seismic responses of the TTLS and identify the most unfavorable FCL.Furthermore,a finite element model(FEM)is developed and its accuracy is validated by comparing it with the experimental results.Parametric analyses are conducted to explore the effects of fault crossing angles(FCAs)and PGMD amplitudes on the seismic performances of TTLSs.This study is expected to contribute valuable insights for the seismic design and performance analysis of TTLSs crossing fault areas.
基金Project supported by the National Natural Science Foundation of China (No. 50638010)the Specialized Research Fund for the Doctoral Program of Higher Education of China (No. 20070141036)
文摘Collapses of transmission towers were often observed in previous large earthquakes such as the Chi-Chi earthquake in Taiwan and Wenchuan earthquake in Sichuan,China. These collapses were partially caused by the pulling forces from the transmission lines generated from out-of-phase responses of the adjacent towers owing to spatially varying earthquake ground motions. In this paper,a 3D finite element model of the transmission tower-line system is established considering the geometric nonlinearity of transmission lines. The nonlinear responses of the structural system at a canyon site are analyzed subjected to spatially varying ground motions. The spatial variations of ground motion associated with the wave passage,coherency loss,and local site effects are given. The spatially varying ground motions are simulated stochastically based on an empirical coherency loss function and a filtered Tajimi-Kanai power spectral density function. The site effect is considered by a transfer function derived from 1D wave propagation theory. Compared with structural responses calculated using the uniform ground motion and delayed excitations,numerical results indicate that seismic responses of transmission towers and power lines are amplified when considering spatially varying ground motions including site effects. Each factor of ground motion spatial variations has a significant effect on the seismic response of the structure,especially for the local site effect. Therefore,neglecting the earthquake ground motion spatial variations may lead to a substantial underestimation of the response of transmission tower-line system during strong earthquakes. Each effect of ground motion spatial variations should be incorporated in seismic analysis of the structural system.
基金Research Fund of Chinese State Grid Company (No.SGKJ[2007]413)
文摘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.
文摘风雨载荷对输电塔线体系的安全性有着重要影响.本文对某110kV输电线路中塔线耦联体系在风雨载荷作用下的动力特性进行分析.首先,在Ansys软件中建立某110 k V输电塔线体系有限元模型,并进行模态分析.其次,结合Davenport风速谱与雨载荷相关理论,在Matlab中生成与加载节点对应的风雨耦合载荷.最后,研究在此耦合载荷下的塔线体系的动力响应,并探究在不同风向角和有无雨载荷的情况下其动力响应的结果.结果显示:导地线在整体上增加了塔线体系刚度,但由于其自身在横线方向具有较强“舞动效应”,导致其在横线方向和顺线方向耦联效应有所不同;90°风向角为塔线体系最不利风向角,此时塔线体系动力响应达到最大值;在降雨量为20mm/h的情况下,计及雨载荷将增加塔线体系动力响应范围约为5%~10%,雨载荷对单塔的作用几乎可以忽略不计,其主要是通过加剧导地线的“舞动效应”,进而增加塔线体系的动力响应.
文摘架空输电线路设计过程中,人工计算塔腿坐标与占地范围的shapefile(SHP)文件成图效率低、错误率高。针对这一问题,提出一种基于开源地理信息系统(geographic information system,GIS)库的自动化绘图方法,该方法不仅建立塔腿坐标计算的几何模型,还利用地理空间数据抽象库(geospatial data abstraction library,GDAL)/矢量数据处理库(OpenGIS Simple Features Reference Implementation,OGR)实现从杆塔参数到占地范围SHP文件的批量生成与可视化。西藏某500 kV线路工程的应用表明:该方法计算的塔腿坐标中误差为0.2 mm,实现了全流程、自动化塔位绘图,大幅提升了工作效率与数据准确性,而且软件安装便捷,具有良好的推广应用价值。
