• Journal of the Korean Ceramic Society
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• v.36 no.3
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• pp.260-265
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• 1999

보통 포틀랜드 시멘트와 플라이애쉬, 슬래그를 혼합한 혼합시멘트 경화체를 이용하여 이온 확산에 미치는 혼합재의 영향과 양이온 공존시 염소이온의 확산에 대하여 고찰하였다. 겉보기 이온확산계수가 보통 포틀랜드의 시멘트보다 플라이애쉬와 슬래그를 혼합한 시멘트 경화체가 약 10-3배로 매우 낮은 값을 나타내었다. 이것은 포졸란 반응에 의해 많은 CSH 수화물이 capillary pore에 형성되어 macro pore가 감소되고 micro pore가 증가되어 이온 확산에 대한 저항이 커졌기 때문이다. 또한, Mg2+이온 공존시에 염소이온의 확산은 증가되었다.

• Journal of the Korea Institute of Building Construction
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• v.13 no.3
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• pp.218-226
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• 2013

Of construction materials, cement and steel are the representative material that carbon dioxide. to reduce carbon emissions in the use of these materials The purpose of this study is low heat type blended cement, which is manufactured using a amount of cement than ordinary low heat blended cement. Low heat blended cement, mixing ratio of 10%, was investigated hydration properties and adiabatic temperature of concrete. The study in order to activate the reaction mineral admixture, a separate source of CaO and $SO_3$ areneeded. gypsum and lime, it expected amount of cement, low-carbon low-heat blended cement could reduce the hydration heat concrete than currentlyused low heat blended cement.

• Cement
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• s.73
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• pp.37-40
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• 1978

• Cement
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• s.130
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• pp.20-25
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• 1993

• Resources Recycling
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• v.12 no.5
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• pp.23-28
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• 2003

Converter slag was reduced and modified with the addition of 5~10 weight percent of $SiO_2$, $Al_2O_3$ and $SiO_2+Al_2O_3$. which was water quenched and used as a cement additives. Additive was mixed from 10 to 30 weight percent with ordinary portland cement and made 9 kinds of mixed cement. Compressive strength of mixed cement mortar was tested md compared with com pressive strength of ordinary portland cement mortar. Effect of hydration reaction on the compressive strength of cement mortar was investigated by means of x-ray diffraction and scanning electron microscopy.

• Journal of the Korean Geosynthetics Society
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• v.14 no.4
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• pp.159-165
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• 2015

In this study, the coefficient of permeability for cement mixtures including the powdered sludge of basalt, sand or fly ash with different mixed ratios was measured in order to reuse the powdered sludge of basalt in Jeju Island as the cut off materials. As the permeability test results, the coefficient of permeability for the cement mixtures with fly ash was increased with increasing the fly ash contents. The amount of fly ash in the cement mixtures should be mixed with less than 8 %. Meanwhile, the coefficient of permeability for the cement mixtures with sand was increased with increasing the sand contents. The amount of sand in the cement mixtures should be mixed with less than 40 %. According to the comparison result of cement mixtures including fly ash or sand, it is more advantageous to put the sand into the cement mixtures, rather than mixing the fly ash.

• Cement Symposium
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• s.49
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• pp.29-30
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• 2022

Since the climate problem getting severe, carbon neutrality is rising global issue. The limestone powder addition that can substitute clinker in cement is look forward to get positive effect as filler. This study focus on the effect of limestone powder chemical characteristic on mortar workability and compressive strength. Consequently, regardless of type of limestone and subsitution amount, the compressive strength was lower then OPC. But the workability of limestone composite cement showed higher then OPC. Considering latter strength development, using unit water decreasing effect of limestone composite cement is planned further.

• Cement Symposium
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• no.25
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• pp.85-93
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• 1997

• Cement Symposium
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• no.25
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• pp.150-153
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• 1997

• Journal of the Korean Chemical Society
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• v.55 no.3
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• pp.490-494
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• 2011

This paper reports the use of supplementary cementing materials (SCMs) derived from local resources, for the partial replacement of Portland cement to reduce $CO_2$ emission during cement production. Replacement of Portland clinkers up to 20 wt.% with SCMs in normal cements reduced $CO_2$ emission by 0.18 kg $CO_2$/kg. The compressive strength exceeded the standard specification for Portland cement ASTM C-150. Blended cement samples containing 20% Portland clinker replacement had compressive strengths of 37 MPa after 28 days of curing time. The microstructure evolution of blended cement at a composition of 80:20 was similar to that of the 100% Portland cement, where the structure between days 28 and 56 reached a steady state. Blended cements with compositions of 70:30 and 60:40 still showed progress of CSH plate formation and the lack of massive structure development. It is shown that the use of supplementary cementing materials could be as one of alternative ways to reduce $CO_2$ emissions during cement production.