• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2004년도 춘계 학술발표회 제16권1호
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• pp.450-453
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• 2004

The present study is a basic experiment on the estimation of the compression strength of high strength concrete, aiming at estimating the compression strength of mass test pieces of high strength concrete by giving the temperature hysteresis of the mass test pieces to managerial test pieces. Thus, this study made concrete test pieces in an optimal mix ratio for each strength level, and also created adiabatic curing tank and managerial test pieces. Then it carried out comparative analysis in relation to core strength and suggested equipment and a technique that can control the strength of high strength concrete mass more conveniently and accurately.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2014년도 추계 학술논문 발표대회
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• pp.19-20
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• 2014

This study is to find out the tensile strength and bonding strength of VAE powder as a preliminary study for the application of the powder to the high strength concrete. The result of the study showed that the compressive strength decreases when more polymers is put into the concrete. On the other hand, it showed that the tensile strength and the bonding strength get improved when the more polymers are put into the concrete. Especially in case of the mixture for high strength concrete, it was found out that more strength is produced than the ordinary concrete.

• 한국건축시공학회지
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• 제2권2호
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• pp.145-150
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• 2002

The hydration of cement paste occurs when the cement is miked with water. During the hydration, hydration heat causes the thermal stress depending on the site of concrete and the cement content. Especially in the high-strength concrete, we must give care to the concrete due to its large cement content. In this study conduction calorimeter and concrete insulation hydration heat meter were used to investigation the hydration heat characteristics of cement and concrete. To reduce hydration heat of high-strength concrete, several types of replacement of fly-ash and blast-furnace slag powder were used in this experiment. As a result of this study, it was found that hydration heat of high-strength concrete was reduced by replacement of fly-ash and blast-furnace slag powder. In case of high-strength concrete using blast-furnace slag powder, the max-heat arrival time was delayed but an effect of heat reduction was lower than a case of high-strength concrete using fly-ash, because it was considered that the heat-dependence property of blast-furnace slag powder was higher than that of fly-ash.

• 콘크리트학회지
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• 제3권4호
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• pp.107-115
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• 1991

플라이애쉬를 혼입한 고강도 콘크리트의 초기 및 장기 강도 특성과 작업성 특성에 관한 연구를 수행하였다. 이를 위하여 강도 수준이 다른 6종류의 기본 배합을 선정하고 각 기본 배합을 선정하고 각 기본 배합에 대하여 플라이애쉬 첨가량을 0, 10, 20, 30%로 변화시켜 가면서 그 특성을 실험하였다. 또한, 고강도 플라이애쉬 콘크리트의 슬럼프 감소현상을 분석하기 위하여 4종류의 배합을 추가하여 실험하였다. 연구 결과, 제2종 포틀랜드 시멘트를 사용한 경우, 플라이애쉬를 10%혼입한 콘크리트는 대부분 28일 이전에 일반 콘크리트보다 높은 강도를 발현하였다. 또한, 플라이애쉬 첨가량이 증가함에 따라 보통강도 콘크리트의 슬럼프값은 감소하였으며, 고강도 콘크리트의 슬럼프값을 일정하게 유지시키기 위해서는 더 많은 양의 고유동화제가 사용되었다.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1996년도 봄 학술발표회 논문집
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• pp.18-23
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• 1996

Since at least three-quarters of the volume of concrete is occupied by aggregate, it is not surprising that its quality is considerable importance. Not only may the aggregate limit the strength of concrete, as weak aggregate cannot porduce strong concrete, but the properties of aggregate greatly affect the durability and sructural performance of concrete. But, it is ture that aggregate strength is usually not a factor in normal concrete strength because the aggregate particle is several times stronger than the matrix and the transition zone in concrete. This study is to consider the influence the strength of concrete according to the kinds of aggregate, such as crushed river rocks, curshed rocks, high strength recycled aggregate, low strength recycled aggregate at water cement ratio 0.25. It is possible to concern the important of the mechanical role of aggegate for the high strength concrete.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1993년도 봄 학술발표회 논문집
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• pp.79-88
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• 1993

The purpose of this study is to provide a firm base for the quality improvement of high strength concrete and the development of ultra high strength concrete as well as enviromental con-servation and utilization of byproducts from industrial processing such as Fly ash and Silica fume. A comprehensive experimental study was performed to investigate the effects on the quality improvement of high strength concrete using mineral admixtures. As results, 400~500kg/$\textrm{cm}^2$ compressive strength and excellent flowability can be obtained if fly ash is replaced with cement in the range of 305. In case of using powder type silica fume, 600~700 kg/$\textrm{cm}^2$ compressive strength is showed and 600~800kg/$\textrm{cm}^2$ compressive strength cam be obtained with liquid type silica fume. But it is necessary to increase dosage of high range water reducer for flowability using powder type silica fume. Especially, higher strength concrete cam be obtained when maximum size of coarse aggregate is lower than 25mm.

• Steel and Composite Structures
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• 제10권5호
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• pp.373-383
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• 2010

This paper presents the experimental studies of the flexural behavior of steel-concrete composite beams. Herein, steel-concrete composite beams were constructed with a welded steel I section beam and concrete slab with different material strength. Four simply supported composite beams subjected to two-point concentrated loads were tested and compared to investigate the effect of high strength engineering materials on the overall flexural response, including failure modes, load deflection behavior, strain response and interface slip. The experimental results show that the moment capacity of composite beams has been improved effectively when high-strength steel and concrete are used. Comparisons of the ultimate flexural strength of beams tested are then made with the calculated results according to the methods specified in guideline Eurocode 4. The ultimate flexural strength based on current codes may be slightly unconservative for predicating the moment capacity of composite beams with high-strength steel or concrete.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2006년도 추계 학술논문 발표대회 논문집
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• pp.107-110
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• 2006

The purpose of this study is to suggest a reference data for the development of high workable and normal strength concrete using Polycarboxylate superplasticizer and granulated blast furnace slag as concrete admixtures. So in this study, it is quantitatively evaluated the workability, compressive strength, the heat of hydration and dry shrinkage of high workable concrete on normal compressive strength($21{\sim}27MPa$) for the practical use in construction field. As a result of this study, it is appeared that the performance of high workable and normal strength concrete is superior than that of ready-mixed concrete of the same strength through the B/P tests in the plants.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2008년도 춘계 학술논문 발표대회
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• pp.21-25
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• 2008

It is the aim of this study to investigate the fire resistance design Guidelines for high-strength concrete structure for example compressive strength more than 40Mpa. It is well know that explosive spalling due to fire attack of high strength concrete is related to concrete failure. so, the purpose of this study introduce the fire A Studty on the Fire Resistance Design Guidelines for High-Strength Concrete Structures of AIK for the response of explosive spalling of high strength concrete.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2005년도 봄학술 발표회 논문집(II)
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• pp.25-28
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• 2005

The experimental results on the mechanical behavior of high-strength concretes subjected to high temperature were presented. Main variables were heating temperature, heating continuance time, and cooling condition. The compressive strength properties of high strength concrete(HSC) varied differently with temperature than those of normal strength concrete(NSC). HSC had higher rates of strength loss than NSC in the temperature range of between $20^{circ}C$ and $400^{circ}C$. Especially, HSC exploded in $400^{circ}C$ of high temperature.