• 콘크리트학회논문집
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• 제16권6호
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• pp.859-865
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• 2004

In this study, the diffusion of chloride ions in cement concrete made with and without the limestone powder was investigated. In order to study the effect of the limestone powder, all mixtures were prepared at a fixed water-cementitious ratio (0.45). From the experimental results, the setting time of limestone powder concrete is faster than that of control concrete, and compressive strength of all specimens decreased with increasing replacement ratio of limestone powders. The diffusion properties of limestone powder concretes indicated a trend increasing with curing period. LSA10 and LSA20 concretes, the diffusion coefficient was smaller than that of control concrete. The addition of $10-20\%$ limestone powder reduces the diffusion coefficient of chloride ions, irrespective of fineness levels of limestone powder.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2003년도 가을 학술발표회 논문집
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• pp.82-85
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• 2003

This study is to investigate durability in concrete containing slag powder and limestone power. The variables are the substitution ratio of slag powder and limestone powder. In order to study the effect of slag powder and limestone powder, all mixtures were prepared at a fixed water/cement ratio, slump, and entrained air quantity. When concrete containing slag powder is mixing rate 40%, durability appeared the highest in general. When concrete containing limestone powder is mixing rate 10% in all experiments, the most suitable result appeared.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2002년도 가을 학술발표회 논문집
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• pp.75-80
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• 2002

This study is to investigate the characteristic on the resistance of chloride infiltration concrete containing limestone powder The variables are the substitution ratio of slag powder and limestone powder. In order to study the effect slag powder and limestone powder, all mixtures were prepared at a fixed water/cement ratio, slump, and entrained air quantity. As results show that the strength and the resistance of chloride infiltration in concrete substitution 10%, 20% limestone powder, and 30%, 40% slag powder are positive.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1999년도 학회창립 10주년 기념 1999년도 가을 학술발표회 논문집
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• pp.85-88
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• 1999

We tested the limestone powder as a filler powder for the effective use of slag cement. Hydration process were investigated by measuring the thermal differential analysis(DTA), compressive strength, XRD patterns, calorimeter of slag cement-limestone powder paste prepared by mixing limestone powder-slag cement. The results obtained in this study, there were no significant difference between the cases of adding up to 5% limestone powder, but the reaction time was accelerated. Also the compressive strength was increased for adding up to 5% limestone powder. The min hydrated paste products were Ca(OH)2 and calcium silicate hydrates. In the case of mixed limestone powder peak appear tricalcium carboaluminate hydrate in the sample of 7 days hydration.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2002년도 가을 학술발표회 논문집
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• pp.369-374
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• 2002

In this paper, setting and hydration heat development characteristics with three binder types, type IV cement＋fly ash, type IV cement＋slag powder and type IV cement ＋ limestone powder. were investigate. As results, it was shown that the limestone powder decreased the initial setting time regardless of replacement ratio, especially the range of 20~50% replacement ratio, and the 2nd peak was shifted ahead when the limestone powder replacement ratio increased. But for the f1y ash and the limestone powder, contrary results were obtained compared with the limestone powder.

• 콘크리트학회논문집
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• 제16권3호
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• pp.433-440
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• 2004

In order to improve the performance of concrete, generally, modern cements often incorporate several mineral admixtures. In this study, the experimental included the flow value, air content of mortar containing limestone powder and length change and compressive strength of mortar specimen immersed in sulfate solutions. From the experimental results, the limestone powder cement matrices improved the physical properties and sulfate resistance of cement matrices at $10\%$ replacement ratio of limestone powder. The $30\%$ replacement ratio of limestone powder was significantly deteriorated in sodium sulfate solution. Irrespective of fineness levels of limestone powder, length change and SDF of mortar specimens with only $10\%$ replacement was much superior to the other replacements.

• 콘크리트학회논문집
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• 제16권3호
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• pp.303-310
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• 2004

본 연구는 국내에서 생산되는 석회석미분말을 콘크리트의 혼화재료로서 사용하기 위한 기초연구로의 일환으로 석회석미분말의 첨가방법, 첨가율 및 물-분체비 등이 강도발현 및 황산염 침해에 대한 저항성에 미치는 영향을 검토하였다. 그 결과, 석회석미분말을 시멘트에 대해 치환하여 사용하는 경우, 치환율이 증가할수록 강도는 저하되나, 단위시멘트량에 의해 강도가 거의 결정된다. 이런 석회석미분말의 시멘트 치환인 경우는 콘크리트의 수화열이 저감되어 매스 콘크리트에 유효하게 이용 가능할 것으로 판단된다. 그리고 석회석미분말을 잔골재에 대해 치환하여 사용하는 경우, 치환율이 증가할수록 강도와 황산염 침투에 대한 저항성이 증가하며, 이와 같은 석회석미분말을 사용하는 방법은 고강도콘크리트 및 황산염 침투에 대한 저항성이 우수한 콘크리트를 제조하는 데 유효하게 이용 가능할 것으로 판단된다.

• 한국도로학회논문집
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• 제14권4호
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• pp.37-49
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• 2012

PURPOSES : This study is to investigate the fundamental properties of limestone added cement concrete for application of pavement. METHODS : As the production of Portland cement causes environmental problems, engineers have sought more environment-friendly concrete construction materials. Limestone powder can be used for concrete as a partial replacement of Portland cement. One of the great applications of limestone powder added cement concrete might be a cement concrete pavement since the concrete pavement consumes massive quantity of Portland cement. Experimental variables were different replacement level of limestone powder by 0% to 25% with 5% increment. Before hardening of fresh concrete, setting time and plastic shrinkage characteristics were investigated in addition to other basic properties. Properties of hardened concrete included compressive, tensile and flexural strength as well as drying shrinkage. RESULTS : The addition of limestone powder did not significantly affect the properties of fresh concrete. Strength deceased as the replacement ratio increased and when the replacement ratio was greater than 10% decrease rate increased. CONCLUSIONS : It was found that the partial replacement of the limestone powder to cement in pavement materials can be positively considered as its mechanical properties show comparable performance to those normal concrete.

• 한국세라믹학회지
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• 제50권2호
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• pp.149-156
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• 2013

This study examines the effects of limestone's factors on the fluidity of cement paste when of up to 15%. As the substitution ratio of limestone powder increases, the fluidity of the paste is also improved; however, it has no correlation to the $CaCO_3$ content of the limestone, fineness of the limestone, and fluidity of the pastes. Regardless of clay content of the limestone, it showed a similar mini-slump, so there was no correlation between the clay content and the fluidity of the paste. Also, the total organic carbon content of the limestone and the fluidity of the paste showed no correlation. Regardless of the limestone's grade or fineness, n value of powder gained by using the Rosin-Rammler distribution function showed that the fluidity of the paste increased as the n value reduced. It was also shown that particle size distribution of ordinary Portland cement with limestone powder had a major effect on the fluidity of the paste.

• 한국건설순환자원학회논문집
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• 제12권1호
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• pp.102-109
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• 2024

석회석미분말을 콘크리트용 재료로 활용하기 위하여 치환율을 달리하여 제조한 시멘트 경화체의 역학적 특성 및 내구특성을 평가하였다. 일반적으로 석회석미분말은 시멘트 수화반응에 기여하지 못함으로 이를 사용한 모르타르의 압축강도 시험결과 치환율이 증가할수록 압축강도는 감소하였다. 그러나 석회석미분말을 사용한 모르타르의 염소이온 침투저항성, 탄산화저항성 및 화학저항성 등 내구성능을 평가한 결과 석회석미분말의 작은 입자가 시멘트 경화체 내부의 미세한 공극을 채워주는 마이크로 필러효과로 인하여 치환하지 않은 기준 모르타르에 비하여 우수한 결과를 나타내었다. 따라서 석회석미분말은 콘크리트의 내구성 향상을 위한 효과적인 방법으로 활용될 수 있을 것으로 기대된다. 본 연구에서는 석회석미분말의 치환량을 0 %, 5 %, 10 %, 15 %로 변화시켜 내구성능을 평가하였으나 향후 석회석미분말의 종료와 치환량을 다양한 수준으로 변화시켜 내구성능에 미치는 영향을 보다 자세히 연구할 필요가 있을 것으로 판단된다.