• Proceedings of the KIEE Conference
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• 2003.11a
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• pp.20-22
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• 2003

This paper focuses on the effects of wind pressure on transmission towers. It recommends the need for an application method to strengthen some existing towers, especially those in areas regularly affected by typhoons, and to be applied to new constructions. Some considerations taken into account were modifying existing towers exposed, which can cause significant damage to the power system and the effects of damage on third parties.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2008.04a
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• pp.337-340
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• 2008

There were two transmission tower collapses due to Typhoon 'Maemi' in 2003. The reason that a collapse was happened was excessive wind load. One was buckled in the leg part and the other was buckled in the middle bracing part. To investigate a steel transmission tower failure mechanism, 2nd order nonlinear analysis should be performed. Considering the effect of initial imperfection and theresidual stress of angle section during nonlinear analysis, this study can estimate the ultimate strength and the ultimate behavior of the transmission tower.

• 한국방재학회:학술대회논문집
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• 2007.02a
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• pp.75-78
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• 2007

The structural methodology in designing a transmission tower have been performed to assume a simple truss behavior. But there're quite differences between a simple truss behavior and a real one. A suitable explanation for a structural stability can be expressed as a semi-rigid connection instead of the assumed hinged connection. This study proposes an alternative structural analysis modelling strategy for the transmission tower design. Proposed element models are truss element model, beam element model, and combined beam-truss element model. The static finite element analysis shows that there's a moment distribution between a mainpost member and the other bracing member.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 1994.04a
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• pp.171-180
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• 1994

Full scale structural test of 765kv electric transmission tower was performed to measure the stresses and displacement of towers under the design loadings, and the results were compared with analytical results based on three dimensional frame analysis. Also, the actual ultimate strength of the tower was measured through destructive test. Especially, to predict the behavior and failure of the connection of tubular member, finite element analysis was performed and compression test for the segments of tubular member were carried out. Valuable information for the overall and local behavior of the tower was obtained and reliability of current analytical method was confirmed.

• Proceedings of the Korean Geotechical Society Conference
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• 2010.09a
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• pp.605-614
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• 2010

In this paper, the initial behavior of transmission tower was analyzed. This tower was firstly constructed by rock anchor foundation in domestic 154 kV transmission line and wireless real-time monitoring system was installed to obtain the measured data for analysis of the structure behavior. For this purpose, 16 strain gauges was installed in anchors of foundation and strain gauges, clinometers, anemoscope and settlement sensors was installed at superstructure. As the results, the main factor which influence the behavior of superstructure is wind velocity, wind direction, rainfall and temperature change. Especially, the uplift load at stub of transmission structure revealed about 35.4 percentages of design load. Hereafter the long term stability will be analyzed.

• Proceedings of the KIEE Conference
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• 2011.07a
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• pp.471-472
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• 2011

최근 10여년간 기후변화로 인한 낙뢰빈도와 낙뢰크기가 증가추세로 분석되고 있으며 이로 인해 한전의 전력설비는 낙뢰고장 점유율이 크게 증가하고 있다. '96년~'00년 사이에 59.3%이었던 낙뢰고장 점유율이 최근 5개년('06~'10년)사이에 무려 80.3%에 이르고 있는 실정이다. 또한 민원으로 인한 산악지 경과 및 4회선 송전철탑의 증가로 낙뢰 고장의 개연성은 계속 증가하고 있다. 따라서 본 논문에서는 실제 한전설비에 발생했던 과거 10년간의 고장자료를 심층 분석하여 낙뢰고장을 감소시킬 수 있는 개선 아이디어를 도출하고 향후 낙뢰고장 분석에 필요한 추가 핵심인자를 발굴해보고자 한다.

• Journal of the Korean Geotechnical Society
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• v.17 no.3
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• pp.77-82
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• 2001

반복하중을 받는 현장타설말뚝에 대한 두 가지의 주요 관심사항은: (a) 지지력의 변화 가능성 그리고 (b) 누적변형량에 의한 기초의 가능성 저하이다. 이러한 인자들에 대한 평가를 위하여, 모형점토지반에 설치된 24개의 모형현장타설말뚝에 대한 정적 및 동적경사재하시험(12개의 압축 및 12개의 인발)을 수행하였다. 경사반복압축재하시험에서는 반복하중에 의한 지지력의 변화가 무시할 정도였으며, 누적변형량은 송전철탑의 기능성에 영향을 줄수도 있을 것으로 사료된다. 그러나, 경사반복인발시험에서는 과도한 누적변형이 발생하게 되어 결과적으로 현장타설말뚝주변과 점토사이의 접촉면적이 감소하는 것으로 나타났다. 접촉면적의 감소 결과, 반복경사인발하중에 의해서 경사인발지지력의 현저한 감소가 일어난다는 사실을 알 수 있었다. 정적경사인발지지력의 50에서 70퍼센트에 해당되는 반복하중을 받는 대부분의 현장타설말뚝들은 인발되었다.

• Proceedings of the Korean Geotechical Society Conference
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• 2005.03a
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• pp.687-696
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• 2005

Safety diagnosis was conducted to evaluate the long-term stability evaluation of power transmission tower of which deformation of the upper structural elements occurred. To assess the cause of the structural deformation, field investigation including BIPS, down-hole test, concrete pile coring and finite element analysis were carried out. From these studies, the major cause of deformation was found due to the heavily fractured layer and weathered soil topography at the pile tip area. The cement-milk grouting method was proposed to reinforce these weak zone around the pile tip area. Also, the increase of cross-section and stiffness for steel members of upper tower structures was suggested. Instrumental monitoring was proposed as well to verify reinforcing effect.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.57 no.2
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• pp.179-183
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• 2008

In case of a line-to-ground fault at transmission lines, a portion of fault current will flow into the earth through the footings of the faulted tower causing electrical potential rise nearby the faulted tower footings. In this situation, any buried pipelines or structures nearby the faulted tower can be exposed to the electrical stress by earth potential rise. Although many research works has been conducted on this phenomena, there has been no clear answer of the required separation distance between tower footings and neary buried pipeline because of its dependancy on the soil electrical charactersics of the concerned area and the faulted system. In this paper, an analytical formula to calculate the requried sepeartion distance from the faulted tower has been derived.

• Proceedings of the KIEE Conference
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• 2015.07a
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• pp.290-291
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• 2015

병행하는 가공송전선로에서 휴전된 선로에 유도되는 전압은 수백에서 수만 볼트에 이른다. 이 때문에 휴전된 선로의 작업을 위해 선로의 양단 발 변전소에서 접지개폐기를 통하여 선로 접지를 하는 것은 물론 잔류 유도전압 제거를 위해 선로작업구간 근처 양단 철탑에도 접지를 시공하고 선로작업을 시행한다. 선로작업 완료 후 가압 시 발 변전소의 접지개폐기 개폐상태는 근무자가 감시제어시스템을 이용하여 확인 가능하다. 개폐기간 인터록시스템으로 접지상태에서 선로가압은 불가하지만, 선로에 작업자가 설치해 놓은 접지선이나 접지설비 등은 발 변전소 운전자가 접지제거 상태를 작업자에게 인위적으로 확인한 후 가압하는 방법으로 인하여 인적 실수에 의한 접지 중 가압되는 선로고장이 종종 발생되고 있다. 이러한 고장을 방지하기 위한 선로 상 접지 모니터링 시스템의 필요성이 있다.