• 한국세라믹학회지
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• 제44권2호
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• pp.103-109
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• 2007

In this study, the rheological properties of cement pastes containing blastfurnace slag of different fineness were investigated. The fluidity of cement pastes with low Blaine value blastfurnace slag was increased with decreasing the plastic viscosity and the yield stress of pastes. And the optimum dosage of polycarboxylate type superplasticizer to the cement pastes was confirmed according to the fineness and the replacement ratio of blastfurnace slag. All cement pastes showed the thixotropy behavior. And also it was formed that the segregation range of cement pastes was occurred below $10D/cm^2$ of the yield stress and below 350 cPs of the plastic viscosity by the coaxial cylinder viscometer.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1999년도 봄 학술발표회 논문집(I)
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• pp.64-69
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• 1999

Slags are by-products of the metallurgical industry. The most important slag from the standpoint of the quantity used as building material is iron blastfurnace slag. Slags are either crystalline stable solid used as aggregates or glassy material used as hydraulic binder. Slag cements are low heat of hydration cements. Slags react more slowly with than portland cement but they can be activated chemically. Activatiors can be either alkaline activators such as soda, lime, sodium carbonate, sodium silicate or sulphate activators such as calcium sulphate or phosphogypsum. So, in this study slaked lime was used as an activator that the compressive strength of this modified cement(M1 type) is high range in early age. And initial setting time of M1 type cement was shorter than conventional cements.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1995년도 가을 학술발표회 논문집
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• pp.113-118
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• 1995

The purpose of this study is to suggest concrete mix proportioning design using Blast-furnace slag cement. The mix conditions are specified by concrete strength(180~400kg/$\textrm{cm}^2$), slump$(15\pm2cm)$m and air volume$(4.5\pm1%)$. From the result of concrete mix proportioning design using Blast-furnace slag cement, unit water content can be reduced by 3~8% comparing with OPC. The relationship between strength at 28days and cement water ratio is as follow. when blast-furnace slag cement is used: $\sigma_{28}$=304.OC/W-296.8. Super-plasticizer have to be used to get a slump of 15cm when water/cement ratio is less than 45%.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1997년도 가을 학술발표회 논문집
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• pp.203-206
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• 1997

In this paper, the properties of Interlocking block contained blast furnace slag cement are compared with that with O.P.C.(ordinary portland cement) and are analyzed under various mix proportions and the dosage of AE agent. According to the experimental results, compressive strength and flexural strength of interlocking block with blast furnace slag cement are lower than that with OPC. Also the strength and the ratio of absorption decrease with higher dosage of AE agent. although interlocking block with OPC has better performance than that of blast furnace slag in the side of quality, it is worth while to use the blast furnace slag as materials of interlocking block considered the side of recycling of resources and economy.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2004년도 학술대회지
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• pp.51-54
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• 2004

This paper investigated the results of mixture proportion and compressive strength of concrete incorporating mineral admixtures. W/B and contents of mineral admixtures were selected as test parameters. According to test results, use of mineral admixtures resulted in a reduction of fluidity and air contents caused by increased fine particles and absorption effect of FA on reduction of AE agent. Thus, increase of SP and AE agent was needed to maintain the same fluidity and air content as plain concrete. At early stage, use of CKD was beneficial to the compressive strength while at 28days. incorporation of FA and BS had favorable effect on the compressive strength.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2018년도 춘계 학술논문 발표대회
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• pp.222-223
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• 2018

Recent government policies are increasing interest in zero-energy housing, a building that minimizes energy consumption (90% reduction). As the importance of building passive performance is emphasized, the role of insulation is increasing as a way to reduce indoor heat loss in order to minimize the use of cooling and heating energy. There are two main types of insulation. Organic insulation is widely used for various construction structures such as construction and industrial due to some merits such as the convenience of construction and construction cost. However, it has been pointed out as a main cause every time a fire accident occurs, Jecheon Sports Center', the fire damage of buildings caused by the use of organic insulation materials is expanding to social problems, so it is urgent to research on nonflammable inorganic insulation materials.

• 한국세라믹학회지
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• 제37권1호
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• pp.70-76
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• 2000

In order to investigate the properties of the blended cement using coarsely ground blasturnace slag blended coements which were substituted from 10 to 70 wt% low Blaine slag powder (2,000 and 3,000 cm2/g) for porland cement clinker were prepared and Cal(OH)2 contents in hydrates hydration heat the fluidity and the compressive strength were measured. As the content of slag was increased the hydration heat and the early strength was decreased and the fluidity of the cement paste was improved. The heat evolution of the cement with 2,000cm2/g slag was lower than that of 3,000 cm2/g slag blended cement. Especially the heat evolution of 60wt% or above slag blended cement was similar to that of belite rich cement.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2022년도 봄 학술논문 발표대회
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• pp.174-175
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• 2022

The blast furnace slag, which is widely used as a cement admixture, has latent hydraulics under the influence of cement hydrate, and fly ash and silica fume mainly cause a pozolane reaction. As a result, the cement structure becomes dense, and it is possible to compensate for defects when concrete is usually made with portland cement alone. When fixing carbon dioxide through reaction with carbon dioxide, the amount of calcium hydroxide in the cement paste is important. The larger the amount of calcium hydroxide, the more active the reaction may occur. It is also an important variable in calculating the depth of neutralization through carbonization. In this study, calcium hydroxide in cement paste using mixed materials was quantified through thermal analysis.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2023년도 가을학술발표대회논문집
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• pp.151-152
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• 2023

Lightweight aggregates has a dry specific gravity of 2.0 or less, which is lower than natural aggregates. Lightweght aggregate is efficient for weight reduction but has low compressive strength. In this study, EIS(electrochemical Impedance Spectroscopy) was used to confirm the ITZ(Interfacial Transition Zone) between the lightweight aggregate and cement paste according to the coated of blast furnace slag powder. As a result of EIS measurement, the correlation between ITZ characteristics and compressive strength was determined. The phase angle of EIS was different depending on the blast furnace slag powder coated of the lightweight aggregate. The surface-cotead lightweight aggregate was improved and the ITZ was strengthened.

• 한국구조물진단유지관리공학회 논문집
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• 제17권6호
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• pp.88-94
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• 2013

시멘트 내 6가 크롬은 피부질환이나 암을 유발할 수 있는 유해한 인체에 유해한 이온으로 잘 알려져 있다. 본 연구에서는 사람에게 영향을 주는 시멘트 내 6가 크롬의 정량적 분석을 하고자 시멘트 및 시멘트 경화체 내 6가 크롬의 고정화에 대해 평가하였다. 국내에서 생산되는 일반 포틀랜드 시멘트 3종과 플라이애쉬, 고로슬래그 미분말, 실리카퓸을 사용하여 수용성 및 산가용성 6가 크롬을 분광광도법으로 측정하였다. 측정결과, 시멘트 내 수용성 6가 크롬의 농도는 10.5-18.9 mg/kg-cement 범위였으며 혼화재료 내 수용성 6가 크롬의 양은 매우 적게 측정되었다. 시멘트 내 산가용성 6가 크롬의 농도는 172.4-318.2 mg/kg-cement 범위로 측정되었으며 수용성 6가 크롬에 비해 증가하였다. 그러나 크롬의 pH에 의존적인 용해 특성에 따라 용매의 pH가 저감된다고 하여 산가용성 6가 크롬의 농도가 항상 크게 측정되지는 않았다. 시멘트 수화 후 수용성 6가 크롬은 2.0 mg/kg-cement 정도로 감소하였으며 이는 크롬산-에트링게이트 생성에 의한 결과임을 확인할 수 있었다.