• 대한전기학회:학술대회논문집
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• 대한전기학회 1999년도 하계학술대회 논문집 E
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• pp.2314-2316
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• 1999

This study describes the results of aging characteristics of polymer insulators through the tracking wheel test. In order to evaluate the reliability of polymer insulators, 4 polymer insulators which used in the field were selected. Electrical tests such as power frequency voltage test, steep-front impulse voltage test were performed after tracking wheel test. Chemical structure and contact angle were measured for investigating an aging characteristics. Although some changes have occurred on the surface of insulator, there are no critical changes between new and tracking wheel tested insulator.

• 한국전기전자재료학회논문지
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• 제21권6호
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• pp.530-537
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• 2008

This paper describes the results of a study on the tracking performance of outdoor insulating materials based on the rotating wheel dip test(RWDT). And, the influence of surface degradation was evaluated through such as measurement of the flashover voltage after and before tracking test, also aspects of surface degradation using scanning electron microscopy. The time to tracking breakdown of treated filled specimen is longer than untreated filled specimen. And, after the RWDT, the surface of specimen by adding untreated filler appeared heavy erosion. It was found that the addition to surface treated filler, the better tracking resistance. In the RWDT, the breakdown specimen is not affected by the dry flashover voltage, despite the fact that the surface degradation of tracking test has different state on each specimen. This suggests that wet flashover voltage play an important role in evaluating of tracking and erosion on the surface degradation in tracking test. And, the flashover voltage of specimen under wet conditions are greatly affected by the salt concentration and degree of degradation by the RWDT Because of hydrophobicity and degree of degradation by the RWDT, the flashover voltage of treated filled specimen is higher than that of untreated filled specimen. Different types of specimen may have different hydrophobicity and their surface state under contaminated conditions may not be the same.

• 한국재난정보학회 논문집
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• 제2권1호
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• pp.39-52
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• 2006

In this paper, an analytical and experimental study was performed in order to determine the effects of interaction between vehicle and structure. Results presented in the paper show that analytical method including moving load effect can investigate the trend of structural response due to dynamic interaction between vehicle and structure. The wheel tracking machine fitted with 2-axle test vehicle can demonstrate more accurate dynamic interaction between vehicle and structure than the wheel tracking machine fitted without 2-axle test vehicle.

• 한국도로학회논문집
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• 제7권2호
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• pp.97-107
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• 2005

반복주행시험에서 얻은 침하깊이와 동적안정도는 아스팔트 혼합물의 소성변형 저항성 평가를 위하여 널리 사용되고 있다. 하지만 바퀴의 재질에 따라 다르게 얻어지는 실정이다. 따라서 본 연구는 반복주행시험시 핵심요소라 할 수 있는 바퀴의 재질에 대하여 연구하였다. 이를 위하여 2종류(7.5mm, 15mm)의 고무바퀴와 고무를 씌우지 않은 강재(Steel)바퀴 한 종류를 사용하였으며, 반복주행시험을 통하여 바퀴재질에 따른 혼합물의 소성변형 저항성을 평가하였다. 또한 반복주행시험에서 얻은 침하깊이와 동적안정도를 Kim test의 변형강도와의 상관성 분석을 통하여 반복주행 시험용 최적 바퀴를 선정하는데 이용하였다. 고무두께가 15mm, 7.5mm, 0mm에 대한 상관성 분석결과 각각 0.7, 0.8. 0.9 이상이 나와 고무를 사용하지 않은 강재바퀴가 변형강도와의 상관성이 가장 높은 값을 보여주어 향후 반복주행시험시 강재바퀴의 사용이 소성변형을 예측하는데 가장 유리 할 것으로 판단된다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2000년도 하계학술대회 논문집
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• pp.119-122
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• 2000

Recently polymer insulators are being used for outdoor high voltage applications. Polymer insulators for transmission line have significant advantages over porcelain and glass insulators, especially for ultra-high voltage transmission lines. Their advantages are light weight, vandalism resistance and hydrophobicity. Polymer insulators are a relatively new technology, but their expected life is still unknown. Therefore these estimating technique are very important. Their life time is related to weathering and operating condition. Multi-aging test is requested because aging factor is occurred by multi-aging than unique aging. The aging test about polymer insulators have mainly carried out by IEC 61109. This paper presents multi-stress chamber experiments and tracking wheel test to examine the tracking and erosion performance of polymer insulator for transmission. Multi-stress testing is able to demonstrate deficiencies of polymer insulator materials and designs, including the nature of interfaces in insulation design. We have investigated IEC 61109 Annex C (5000h aging test) and CEA tracking wheel test as test methods of artificial accelerated aging. The aging degree of polymer insulator is estimated by leakage current, measurement of hydrophobicity degree, damage conditions of insulator surface, withstand voltage test etc.

• 한국산학기술학회논문지
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• 제11권1호
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• pp.250-256
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• 2010

본 연구에서는 차량-교량간의 상호작용 효과가 교량의 동적거동에 미치는 영향을 분석하기 위하여 실험적 연구를 수행하였다. 이를 위하여 차량-교량 간 상호작용이 가능하도록 윤하중 실험 장치를 개발하여 단순교량 형식의 교량을 대상으로 이동 질량 실험을 수행하였다. 이동질량 이론을 이용한 해석 결과와 이동질량 실험의 결과를 상호분석하여 각각의 합리성을 검증하였다. 수행된 실험의 결과를 분석하여 개발된 윤하중 시험기는 차량-교량 간 상호작용에 의한 교량의 동적 거동을 재현할 수 있음을 알았다. 아울러 이동질량 실험의 결과를 분석하여 차량-교량 간 상호작용이 교량의 동적거동에 미치는 영향을 분석할 수 있었다.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2003년도 봄 학술발표회 논문집
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• pp.299-304
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• 2003

In this research, eight waterproofing membranes were selected from commercial market and the tensile adhesive characteristics of the waterproofing system (WPS) on concrete bridge deck were investigated in view of various factor in asphalt pavement. Tensile adhesive strength (TAS) test of different asphalt pavement types showed that TAS of WPS under SMA (Stone Mastic Asphalt) pavement was greater than that under dense asphalt pavement. Tensile adhesive strength (TAS) of sheet membranes was improved as the compaction temperature of asphalt concrete increase, but TAS of liquid membranes were not. TAS of sheet membranes after wheel tracking test were in the order of the sites under wheel path (UWP), before wheel tracking (BWT) and nearby wheel path (NWP), Since TAS of the same WPS of UWP was higher than TAS of BWT, wheel loading had function of pressing WPS resulting in higher adhesive strength, But liquid membranes were variable on types, The feature of detached interface after T AS test showed that sheet types were all detached in between deck concrete and WPS, and liquid types were detached in between asphalt pavement and WPS,

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2005년도 하계학술대회 논문집 Vol.6
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• pp.558-559
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• 2005

Recently, polymer insulators that are used for high voltage applications have some advantages such as light weight, small size, vandalism resistance, hydrophobicity and easy making process. During outdoor service of polymer insulators, the surface of the insulating material is frequently subjected to moisture and contamination that lead to dry band arcing. Their tracking resistance, erosion resistance, end sealing and shed design are very important because dry band arcing causes degradation of polymer surface. In this paper, the tracking property of polymer suspension insulator for power transmission is investigated with CEA tracking wheel test. The diagnosis of insulator sample in tracking test has been analyzed by leakage current, STRI Guide, SEM, FTIR and thermal image.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2000년도 춘계학술대회 논문집 유기절연재료 방전 플라즈마
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• pp.82-85
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• 2000

Polymeric composite insulators are used for outdoor insulation. However, our knowledge about their long-term performance in an outdoor environment is still very limited. The electrical stress caused the surface of these insulators to become degradation. In order to evaluate the tracking resistance of polymer insulators, we performed the tracking wheel test which is recommended by CEA LWIWG-01. And the flashover voltage tests were conducted for understanding electrical characteristics after tacking wheel test. Also, these insulators are studied by characterization methods such as contact angle measurement, SEM, etc.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2001년도 하계학술대회 논문집
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• pp.74-77
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• 2001

In order to investigate the effect of salinity level on tracking characteristics of polymer insulators for distribution power systems, tracking tests were performed by tracking wheel tester under different salt concentration. In this study, 6 kinds of polymer insulators were tested under 2200 ${\mu}\textrm{s}$/cm and 4000${\mu}\textrm{s}$/cm salinity. The salinity level has a significant effect on the tracking characteristics. Namely, most polymer insulators showed the good tracking resistance in case of low salinity level. But, in case of high salinity level some polymer insulators showed the excessive erosion and tracking. These phenomena may come from the different aging mechanism. It can be concluded that too high salinity level is not desirable in aging test of polymer insulators.