• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2000년도 봄 학술발표회 논문집
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• pp.704-709
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• 2000

This study is to test effects of sulfate attack on deterioration of cement mortar. Four tests have been carried out with four types of mortars mixed by ordinary portland cement and sulfate-resistant portland cement containing blast-furnace slag and fly-ash. It was immersed in sulfate solution for 7, 28, 91, and 180 days. from the test results, sulfate attack resistance of cement mortar was improved by admixtures (blast-furnace slag and fly-ash), sulfate-resistance portland cement mortar showed high resistance than ordinarily portland cement at compressive strength, and similar the resistance of sulfate attack with ordinarily portland cement mortar with admixtures.

• 한국안전학회지
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• 제7권4호
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• pp.7-12
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• 1992

The smouldering combustibility of cellulose insulation treated with boric acid-borax-aluminium sulfate as combustion retardants are examined by cigarette ignition method and electrical cardrige heater method. The effectiveness of Aluminium sulfate as a third combustion are acceptable both smouldering resistance and flame resistance at 18% level of all examined formulation. As the proportion of Aluminium sulfate in the formulation was increased, the flame resistance of cellulose insulation was improved.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2003년도 봄 학술발표회 논문집
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• pp.1097-1100
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• 2003

This paper describes the sulfate resistance of cement pastes and mortar with or without ground granulated blast furnace slag (GGBS). Sulfate attack was performed on the cement pastes and mortar, which had been prepared by using a water-binder ratio of 0.45. Variables were the fineness levels of GGBS and the concentrations of two sulfate solution. In this present study, compressive strength and length change were carried out to evaluate the sulfate resistance of GGBS with various fineness levels. From the test results, it can be concluded that the deterioration modes of cement matrix with GGBS were dependent on the exposure solutions. Moreover, the influence of fineness levels of GGBS on the sulfate resistance was somewhat little because of a relative short exposure period.

• 콘크리트학회논문집
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• 제12권5호
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• pp.141-151
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• 2000

Compressive strength, sulfate deterioration factor(SDF) and length change of 5 types of mortars immersed in sodium sulfate solution were observed. As the results of tests, it was found that the sulfate resistance of blended cement mortars were superior to that of portland cement mortars. Pore volume with diameter larger than 0.1 $\mu\textrm{m}$ of 5 types of pastes indicated that the micro-structures of blended cement pastes were denser, due to pozzolan reaction and latent hydraulic properties, than those of portland cement pastes. The XRD, ESEM, EDS and TG analyses demonstrated that the reactants such as ettringite and gypsum were significantly formed in portland cement pastes. Besides, compared with the $Ca(OH)_2$ content of ordinary portland cement pastes immersed in water and sodium sulfate solution, the $Ca(OH)_2$ contents of fly ash blended cement and ground granulated blast-furnace slag cement paste were about 58% and 28% in water, and 55% and 20% in sodium sulfate solution, respectively.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1997년도 가을 학술발표회 논문집
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• pp.307-312
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• 1997

The sea water resistance of cement and concrete must be compared when it used for construction in the ocean. The sea water resistance of the concrete specimens using three types of cements such as ordinary Portland cement, sulfate resistance Portland cement, blastfurnace slag cement were studied. In this study, an accelerated test for access sea water resistance by subjecting the concrete specimens to repeated cycles of concentrated sea water immersion and hot wind drying was employed. This study proved that sulfate resistance Portland cement had higher resistance for sea water.

• 콘크리트학회논문집
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• 제22권2호
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• pp.219-228
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• 2010

하수도, 오 폐수, 토양 속, 지하수 및 해수 등의 환경에 건설되는 콘크리트 구조물은 산 및 황산염에 노출되어 있다. 이 같은 산 및 황산염 침투로 포틀랜드 시멘트 중의 수화생성물과 산 및 황산염 이온이 반응하여 팽창 수화물을 생성함으로써 콘크리트에 팽창 및 균열을 발생시켜, 결국 콘크리트 매트릭스에 손상을 일으킨다. 따라서 이 연구의 목적은 콘크리트의 황산 및 황산염 침투 저항성에 미치는 광물질 혼화재의 영향을 평가하여, 황산 및 황산염 침투에 대한 고저항성 콘크리트를 제시하는 것이다. 이를 위하여 광물질 혼화재의 형태 및 비율을 변화시킨 OPC, 2성분계 및 3성분계의 3가지 종류의 시멘트를 사용하여 물-결합재비 32% 및 43%인 콘크리트를 제조하였다. 제작된 콘크리트 시편은 민물, 5% 황산, 10% 황산나트륨 및 10% 황산마그네슘 용액에 재령 28, 56, 91, 182 및 365일 동안 각각 침지시켰다. 콘크리트의 황산 및 황산염 침투 저항성을 평가하기 위하여 외관변화 관찰과 압축강도 비 및 질량 변화율을 측정하였다. 그 결과, 광물질 혼화재를 혼입한 콘크리트의 황산 및 황산나트륨 침투에 대한 저항성은 OPC 콘크리트 경우 보다 훨씬 우수한 것으로 나타났으나, 황산마그네슘의 경우 비결합재질의 규산마그네슘수화물(M-S-H)의 형성으로 광물질 혼화재를 혼입한 콘크리트가 OPC 콘크리트보다 불리한 것으로 나타났다.

• 한국건축시공학회지
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• 제9권3호
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• pp.109-116
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• 2009

The magnesium sulfate solution digestion test carried out for resistance of concrete containing waste glass powder on magnesium sulfate attack. Moreover, it yielded S.D.F index was used for the criteria of quantitative assessment to the resistance of magnesium sulfate for the purpose of evaluation of chemical deterioration on concrete. Furthermore, to evaluate for micro-cracks within concrete and external corrosion, the weight variation of specimens and the dynamic elasticity were compared and analyzed and also the applicability was examined using the analysis of product of hydration through out observing external deformation and micro-structural deformation.

• 복합신소재구조학회 논문집
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• 제6권2호
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• pp.63-69
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• 2015

It has been well known that concrete structures exposed to chloride and sulfate attack environments lead to significant deterioration in their durability due to chloride ion and sulfate ion attack. The purpose of this experimental research is to evaluate the resistance against chloride ion and sulfate attack of the cementless concrete replacing the cement with ground granulated blast furnace slag. For this purpose, the cementless concrete specimens were made for water-binder ratios of 40%, 45%, and 50%, respectively and then this specimens were cured in the water of $20{\pm}3^{\circ}C$ and immersed in fresh water, 10% sodium sulfate solution for 28 and 91 days, respectively. To evaluate the resistance to chloride ion and sulfate attack for the cementless concrete specimens, the diffusion coefficient for chloride ion and compressive strength ratio, mass change ratio, and length change ratio were measured according to the NT BUILD 492 and JSTM C 7401, respectively. It was observed from the test results that the resistance against chloride ion and sulfate attack of the cemetntless concrete were comparatively largely increased than those of OPC concrete with decreasing water-binder ratio.

• 한국건축시공학회지
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• 제9권1호
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• pp.81-87
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• 2009

The purpose of this study is to investigate the sulfate attack resistance of concrete using the EAF(electric arc furnace) Slag as fine aggregate. In order to figure out the effects of magnesium sulfate solution on the durability of concrete using the EAF Slag as fine aggregate, the experiments for the immerging test in the 10% magnesium sulfate solution was executed by selecting factors such as aging processes, replacement ratio(0, 10, 20, 30, 50%), and duration of immerging. The specimens were made with various EAF slag replacements for fine aggregates and with W/C ratio fixed 0.45. compressive strength and S.D.F(Sulfate Deterioration Factor), weight change, and SEM(Scanning Electron Microscope) were tested. From the test results, EAF slag aggregate treated with accelerated aging is better than treated with air aging. The compressive strength and resistance to the sulfate attack is slightly improved with an increase in the EAF slag aggregate treated with accelerated aging replacement for aggregate.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2015년도 추계 학술논문 발표대회
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• pp.11-12
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• 2015

This study analyzed sulfate resistance of strongly acid-resistant inorganic binder based on industrial byproducts. According to the study experiment, compared to OPC mixture, the mixture of high acid-resistant inorganic binder had excellent chemical resistance against 10% H₂SO₄ solution. In the case of ordinary portland cement, its sample with 28 days of immersion had severe corrosion on its mortar erosion part, and thus external appearance was damaged greatly, and compression strength decreased by around 57% and more.