• 한국컴퓨터산업학회논문지
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• 제9권3호
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• pp.137-142
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• 2008

염소이온 침투로 인해 철근 부식에 가장 큰 영향을 끼치는 인자는 염소이온 표면농도이다. 본 연구에서는 염소이온 표면농도에 따른 염해 진행 정도를 개발한 프로그램을 통하여 해석적으로 접근하였다. 또한 해석 프로그램을 통하여 염소이온 표면농도에 따른 내구수명을 산정하였다. 염소이온 표면농도가 600ppm인 경우도 염소이온 침투 깊이가 32.3mm 정도로 나타났다. 콘크리트의 피복두께를 40mm를 유지한다면 염소이온 표면농도가 600ppm일 때 콘크리트의 내구수명은 167년으로 검토되었다.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2018년도 춘계 학술논문 발표대회
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• pp.27-28
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• 2018

Deterioration of reinforced concrete structures due to salt corrosion is a phenomenon that can be easily seen, and the main reason for deterioration is chloride ion. Therefore, researches are actively conducted to control chlorine ion penetration worldwide. The purpose of this study is to evaluate the chloride ion fixation capacity of Portland cement paste containing Hydrotalcite. For this purpose, cement paste containing 0%, 2.5%, and 5% of Hydrotalcite was sealed and cured for 28 days, and the cured cement paste was crushed. Chloride ion solution was prepared at a concentration of 0.5M using NaCl, and the powdered cement paste was reacted for a specific time in aqueous chloride ion solution. After the reaction, the concentration of the chloride ion aqueous solution was measured using a silver nitrate potentiometric titrator, and the reacted cement paste was analyzed using XRD and FT-IR.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2022년도 봄 학술논문 발표대회
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• pp.49-50
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• 2022

This study examined the potential of halophilic bacteria in reducing the chloride ion concentration within the cement mortars exposed to chloride attack. As a result of the experiment, the compressive strength of mortar with Halomonas venusta showed an equivalent performance to that of counterpart mortars without bacteria. Also, the chloride ion concentration measured in mortars including Halomonas Venusta was 71% lower than that of the counterpart mortars without bacteria.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2003년도 봄 학술발표회 논문집
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• pp.705-710
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• 2003

In this study, to confirm the diffusion coefficient of chloride ion is affected by the concentration of NaCl solution, capacity of voltage, time of an electric current, the diffusion coefficient of chloride ion in concrete was investigated through an electrochemical accelerated test. and the results of these test were compared with the diffusion coefficient of chloride ion by test of sodium chloride solution digestion. As the results of this study, the diffusion coefficient of chloride ion wasn't affected by the concentration of NaCl solution, capacity of voltage, time of an electric current within the range of this study and was similar to the diffusion coefficient of chloride ion by test of sodium chloride solution digestion.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2006년도 추계 학술발표회 논문집
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• pp.573-576
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• 2006

To predict service life of concrete structures exposed to chloride attack, surface chloride concentration, diffusion coefficient of chloride ion, and chloride corrosion threshold value in concrete, are used as important factors. of these, as the diffusion coefficient of chloride ion for concrete is strongly influenced by concrete quality and environmental conditions of structures and may significantly change the service life of structures, it is considered as the most important factor for service life prediction. The qualitative factors affecting the penetration and diffusion of chloride ion into concrete are water-binder(W/B) ratio, age, cement type and constituents, chloride ion concentration of given environment, wet and dry conditions, etc. In this paper the influence of cement type on the diffusion characteristics of chloride ion in concrete was investigated through the chloride ion diffusion test. For this purpose, the diffusion characteristics in concrete with cement type such as ordinary portland cement(OPC), binary blended cement(BBC), and ternary blended cement(TBC) were estimated for the concrete with W/B ratios of 32% and 38%, respectively. It was observed from the test that the difussion characteristics of BBC containing OPC and ground granulated blast-furnace slag was found to be most excellent of the cement type used in this study.

• 한국해안·해양공학회논문집
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• 제23권1호
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• pp.11-17
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• 2011

항만콘크리트 구조물의 내구성 저하의 중요한 요인은 염소이온침투에 의한 철근의 부식이다. 따라서, 항만콘크리트 구조물의 염소이온 깊이와 깊이별 염소이온농도를 정량적으로 파악할 수 있다면, 구조물의 잔존수명을 사전에 비교적 정확하게 평가할 수 있다. 이러한, 구조물에서의 염소이온농도를 예측하기 위해서는 모델식의 개발이 필요하고 모델식은 정확한 현장데이타를 기반으로 한다. 이에 본 연구에서는 현장 항만구조물에 대한 코어시료를 채취하고 본 시료들에 대한 염소이온침투깊이와 깊이별 염소이온농도를 측정하고자 하였다. 시료는 1차로 완도항, 마산항, 인천항에서 채취하였고, 2차로 여수항과 동해항에서 채취하였다. 수직 높이별 영향을 파악하기 위해서 대기부, 비말대, 간만대로 나뉘어 각 층별 8개의 시료를 획득하였다. 채취된 시료중에서 4개는 강도 실험을 실시하였고, 나머지 4개로 내구성 실험을 실시하였다. 2개의 시료에 대해서는 질산은 변색법을 이용하여 염소이온 침투깊이를 측정 하였다. 나머지 2개의 시료는 깊이별로 5 mm 두께의 절편을 채취하고 이를 ASTM C 114의 시험법에 따라 염화물 이온농도를 측정하였다. 측정결과를 바탕으로 지역과 수직위치에 따른 염소이온 침투의 특성을 파악하였다.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2004년도 추계 학술발표회 제16권2호
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• pp.225-228
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• 2004

In order to estimate the chloride ion penetration, the model, which considers diffusion and sorption, is proposed on the basis of Finite Element Method (FEM). The FEM program provides the estimation of chloride concentration according to cyclic humidity and sorption. After the humidity diffusion analysis is carried out, the chloride ion diffusion and sorption analysis are conducted on the basis of the preestimated humidity data in each element. Each element has different analysis variables at different ages and locations. At early ages and constant outer humidity, the difference between inner and outer relative humidity causes the chloride ion penetration by sorption. As the humidity diffusion reduces the difference with age, the effect of sorption on the chloride ion penetration decreases. By the way, the cyclic humidity increases the effect of sorption on the chloride ion penetration at early ages, and the quantity of chloride ion around steel at later ages. Therefore, the in-situ analysis of chloride ion penetration for marine concrete structures must be performed considering the cyclic humidity condition and the long term sorption.

• Ocean and Polar Research
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• 제26권1호
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• pp.43-50
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• 2004

The diffusion model, which considers diffusion and sorption, is proposed. The FEM program developed on the basis of the diffusion model provides the estimation of chloride concentration according to cyclic humidity and sorption. After the humidity diffusion analysis is carried out, the chloride ion diffusion and sorption analysis are conducted on the basis of the preestimated humidity data in each element. Each element has different analysis variables at different ages and locations. At early ages, the difference between inner and outer relative humidity causes the chloride ion penetration by sorption. As the humidity diffusion reduces the difference with age, the effect of sorption on the chloride ion penetration decreases. By the way, the cyclic humidity increases the effect of sorption on the chloride ion penetration at early ages, and the quantity of chloride ion around steel at later ages. Therefore, the in situ analysis of chloride ion penetration for marine concrete structures must be performed considering the cyclic humidity condition and the long term sorption.

• 한국해안해양공학회지
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• 제15권2호
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• pp.71-79
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• 2003

본 논문에서는 염소이온 침투해석에 사용되는 염소이온 확산계수. 염소이온 고정화 관계식, 증발가능 수량에 대한 일반 예측식들을 제시하였다. 이러한 식들을 염소이온 확산 모델링에 대입하여 그 식들의 유효성을 검토하였다. 상대습도와 양생온도의 염소이온 확산에 대한 영향은 주로 확산계수를 변화시켜 고려한다. 상대습도가 증가하면 염소이온 확산깊이는 증가하고 재령이 경과할수록 상대습도가 확산깊이에 미치는 영향은 커진다. 반면에, 양생온도가 증가하면 확산깊이가 조금 증가하지만 재령이 경과할수록 양생온도가 확산깊이에 미치는 영향은 감소한다. 한편, 염소이온의 고정화에 영향을 미치는 시멘트의 $C_3$A양이 증가하면 표면에서는 고정염소이온의 증가로 인해 전체 염소이온량이 증가하지만 깊이가 깊어질수록 확산되는 자유염소이온의 감소로 인해 전체 염소이온량이 감소한다. 물-시멘트비가 감소하면 염소이온의 확산깊이는 급격히 감소하고 염소이온의 확산을 막는 가장 효과적인 방법은 물-시멘트비를 감소시키는 것임을 알 수 있다

• 한국환경과학회지
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• 제2권4호
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• pp.291-297
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• 1993

The COD values and chloride ion concentrations of the Taewha river flowing through Ulsan area were determined along the main stream and the relationships between CODs and chloride ion concentrations were described. The results showed that the middle-upper stream and downstream of the Taewha river were polluted deeply with municipal sewage and self-purification occured in the middle-downstream of the river. When domestic sewage is a main source of pollutants, and is especially the only source of chloride in the stream water, the ratio of COD/[$\textrm{Cl}^{-}$] will be utilizable as a measure of self-purification of the stream.