• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2007년도 춘계학술논문 발표대회
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• pp.129-132
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• 2007

In this study, for the establishment of the performance evaluation methods of repair material and method for reinforced concrete structure and the quality control standards of durability recovery method, the quantitative exposure data by exposure experiment under the coastal and normal atmosphere environment is accumulated and analyzed. Investigating and evaluating the result of exposure experiment during 54 months of exposure age under the coastal and normal atmosphere environment, Micro crack, swelling and spatting of surface coating material, crack of repair boundary parts and the great potential difference between repair part and non-repair part were somewhat generated. And the result shown that exposure specimen of coastal environment had lower electrode potential than exposure specimen of normal atmosphere environment.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2001년도 봄 학술발표회 논문집
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• pp.501-506
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• 2001

An experimental study was carried out to investigate recycling of an oyster shell, which is disposed in open-dumped way at coastal oyster factory area. For this purpose, the chemical component and reaction of oyster shell with cement paste was examined. And, the characteristics of hardened concrete was quantitatively investigated in terms of fineness modulus and blending rate of the crushed oyster shell. Test results show that interaction between oyster shell and cement paste was not occurred and the crushed oyster shell can be used as the fine aggregate of concrete. And it is found that blending of an oyster shell caused not to reduce the 28 day compressive strength of concrete. Elastic modulus of the concrete blended with crushed oyster shells decreases with increases the blending rate which the modulus reduced about 10% when oyster shells is blended up to the 20% of the sand substitution.

• 복합신소재구조학회 논문집
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• 제4권3호
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• pp.13-21
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• 2013

In this study, uniaxial compression tests were performed to investigates the stress-strain relations of Double Skinned Composite Tubular Columns reinforced with steel tube. The confined concrete has been known as the strength of concrete increases significantly. Specimens reinforced with outer and inner steel tube were tested by uniaxial compression test. To investigate the influence of concrete strength increase by confining conditions in steel tubes, 8 specimens with different thickness of tube, hollowness ratio and concrete strength were tested and compared with other researcher's concrete material model.

• 대한원격탐사학회지
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• 제33권4호
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• pp.437-444
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• 2017

Since land pixels often generate false alarms in ship detection using Synthetic Aperture Radar (SAR), land masking is a necessary step which can be processed by a land area map or water database. However, due to the continuous coastline changes caused by newport, bridge, etc., an updated data should be considered to mask either the land or the oceanic part of SAR. Furthermore, coastal concrete facilities make noise signals, mainly caused by side lobe effect. In this paper, we propose two methods. One is a semi-automatic water body data generation method that consists of terrain correction, thresholding, and median filter. Another is a dynamic land masking method based on water database. Based on water database, it uses a breadth-first search algorithm to find and mask noise signals from coastal concrete facilities. We verified our methods using Sentinel-1 SAR data. The result shows that proposed methods remove maximum 84.42% of false alarms.

• 한국해안해양공학회:학술대회논문집
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• 한국해안해양공학회 2002년도 한국해안해양공학발표논문집 Proceedings of Coastal and Ocean Engineering in Korea
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• pp.280-286
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• 2002

염소이온 확산해석을 실제 구조물에 대해서 수행하기 위해서는 여러 변수들에 대한 값들이 필요하다. 이러한 변수들에 대한 값들은 적용 배합에 대한 실험을 통해 직접 측정할 수도 있지만 설계 단계에서 염해에 의한 내구성을 평가를 위해 실험을 수행하기가 실용적인 관점에서 매우 어렵다. (중략)

• 한국해안해양공학회:학술대회논문집
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• 한국해안해양공학회 2002년도 한국해안해양공학발표논문집 Proceedings of Coastal and Ocean Engineering in Korea
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• pp.118-121
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• 2002

항만시설의 기본재료로서 가장 널리 사용되고 있는 피복석 (Rock armor)의 경우 저렴하며, 구입이 용이하다는 장점 때문에 여러 시설물에 적용되어 왔다. 그러나 계속되는 개발로 인해 석재원도 그 한계에 도달했기 때문에 더 이상 저렴한 재료라고 할 수도 없으며, 무엇보다 난 개발로 인한 국토의 훼손과 이에 따른 비난의 여론으로 인해 피복석의 사용이 제한을 받고 있다. (중략)

• 한국해안해양공학회:학술대회논문집
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• 한국해안해양공학회 2002년도 한국해안해양공학발표논문집 Proceedings of Coastal and Ocean Engineering in Korea
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• pp.122-129
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• 2002

근래에 건설공간의 부족과 교통의 편리함으로 인해 해양 콘크리트 구조물의 건설이 증가하고 있다. 이러한 해양 콘크리트 구조물의 내구성에 가장문제가 되는 것이 염해에 의한 철근의 부식이다 염해에 의해 철근이 부식하게 되면 구조물의 안전성이나 사용성에 큰 악영향을 미치게 된다. (중략)

• 한국해안해양공학회:학술대회논문집
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• 한국해안해양공학회 2003년도 한국해안해양공학발표논문집
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• pp.307-314
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• 2003

해양콘크리트 구조물의 내구성에 가장 큰 영향은 미치는 요인 중의 하나가 염소 이온의 침투에 의한 철근부식이다. 염소이온이 콘크리트 구조물 내부로 확산되어 철근이 부식하게 되면 철근의 부피팽창으로 콘크리트 덮개에 균열이 발생하고 철근의 단면적도 줄어들게 된다. 따라서, 구조물은 사용연한을 채우지 못 하고 붕괴되거나 사용성에 큰 문제가 발생하게 된다. (중략)

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2010년도 춘계 학술대회 제22권1호
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• pp.457-458
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• 2010

본 연구는 해안 매립지 지하 콘크리트 구조물의 염해에 대한 피해를 방지하고자 개발한 고내구성 콘크리트(Promoted High Durability Concrete, PHDC)의 기초 물성 및 현장적용성능에 대한 시험 결과를 기술하였으며, PHDC 기술을 토목 및 건축공사 적용시 콘크리트의 물성을 검토하여 회사의 내구성 콘크리트 기준을 제시하였다. 또한 내염해성에 대한 장기 모니터링에 관한 계획을 수립한 후 염분 침투 모니터링 현황을 논문에 기술 하였다.

• Structural Engineering and Mechanics
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• 제77권2호
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• pp.197-215
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• 2021

Under a severe environment of multiple hazards such as earthquakes and winds, the life-cycle performance of engineering structures may inevitably be deteriorated due to the fatigue effect caused by long-term exposure to wind loads, which would further increase the structural vulnerability to earthquakes. This paper presents a framework for evaluating the lifetime structural seismic performance under the effect of wind-induced fatigue considering different sources of uncertainties. The seismic behavior of a high-rise steel-concrete composite frame with buckling-restrained braces (FBRB) during its service life is systematically investigated using the proposed approach. Recorded field data for the wind hazard of Fuzhou, Fujian Province of China from Jan. 1, 1980 to Mar. 31, 2019 is collected, based on which the distribution of wind velocity is constructed by the Gumbel model after comparisons. The OpenSees platform is employed to establish the numerical model of the FBRB and conduct subsequent numerical computations. Allowed for the uncertainties caused by the wind generation and structural modeling, the final annual fatigue damage takes the average of 50 groups of simulations. The lifetime structural performance assessments, including static pushover analyses, nonlinear dynamic time history analyses and fragility analyses, are conducted on the time-dependent finite element (FE) models which are modified in lines with the material deterioration models. The results indicate that the structural performance tends to degrade over time under the effect of fatigue, while the influencing degree of fatigue varies with the duration time of fatigue process and seismic intensity. The impact of wind-induced fatigue on structural responses and fragilities are explicitly quantified and discussed in details.