• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2012년도 추계 학술논문 발표대회
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• pp.263-264
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• 2012

In this study, the ultra high strength concrete which have 100, 150, 200MPa took the heat from 20℃ to 70 0℃ and the 0, 20% stress in normal condition's to evaluate stress-strain, residual compressive strength and thermal expansion deformation were evaluated. The heating speed of specimen was 0.77℃/min 20~50℃, 50℃ before the target temperature, and the other interval's heating speed was 1℃/min. As a result, the stress-strain curve of non-load specimen showed the liner behavior at high temperature when the specimen's strength increased more. If ultra high strength concrete got loads, its compressive strength tended to decrease different from the normal strength concrete. The thermal expansion deformation was expanded from a vitrification of quartz over 500℃. however, over the 600℃, it was shrinked because of the dehydration of the combined water.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2015년도 춘계 학술논문 발표대회
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• pp.59-60
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• 2015

In this study, stress-strain, thermal expansion strain, total strain and high temperature creep strain of ultra-high-strength concrete with compressive strengths of 80, 130, and 180MPa were experimentally evaluated considering elevated temperature and loading condition. Also, transient creep strain has been calculated by using the results of experiment. Experimental coefficient K was proposed with application of non-steady state creep model. It is considered that the experimental results of this study could be baseline data for deformation behavior analysis of ultra-high-strength concrete.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2006년도 추계 학술발표회 논문집
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• pp.449-452
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• 2006

In this study, recently, more highly effective construction materials are needed for a reasonable cause and economical structure system is required as the construction structures become more multi storied, large-sized and diversified. Also, the experiment was not carried out to investigate and analyzed the strength properties and flowability of ultra-high strength accroding to the types of mineral admixtures. Therefore, this is an experimental study to compare and analyze the influence of cementitious materials type on the fluidity and the strength properties of ultra-high strength concrete. For this purpose, it has decided to do the mix proportions of concrete according to the type of cementitious materials (fly ash, blsat furnace slag, silica fume, slag cement) and W/B(23.5, 27.5, 31.5%) has selected. And then we conducted an experiment to find out basic properties of the ultra-high strength concrete such as slump-flow, O-lot and the age of specimens(3, 7, 28, 56days) for compressive strength.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2013년도 추계 학술논문 발표대회
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• pp.34-35
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• 2013

In this study, the ultra high strength concrete which have 80, 130, 180MPa took the heat from 20℃ to 700℃ and the 0, 20% stress in normal condition's to evaluate stress-strain, residual compressive strength and thermal expansion deformation were evaluated. The heating speed of specimen was 0.77℃/min 20~50℃, 50℃ before the target temperature, and the other interval's heating speed was 1℃/min. As a result, the stress-strain curve of non-load specimen showed the liner behavior at high temperature when the specimen's strength increased more. If ultra high strength concrete got loads, its compressive strength tended to decrease different from the normal strength concrete. The thermal expansion deformation was expanded from a vitrification of quartz over 500℃. however, over the 600℃, it was shrinked because of the dehydration of the combined water.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2004년도 춘계 학술발표회 제16권1호
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• pp.288-291
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• 2004

In this paper, to make ultra-high strength SFRCC with the range of compressive strength 180MPa, it was investigated the constitute factors of ultra-high strength SFRCC influenced on the compressive strength. The experimental variables were water-cementitious ratio, replacement of silica fume, size and proportion of sand, type and replacement of filling powder, and using of steel fiber in ultra-high strength SFRCC. As a result, in water-binder ratio 0.18, we could make ultra-high strength SFRCC with compressive strength 180MPa through using of silica fume, quartz sand with below 0.5mm, filling powder and steel fiber.

• 한국융합학회논문지
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• 제11권11호
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• pp.211-217
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• 2020

일반적으로 금형은 소재 부품 분야에서 제품의 대량 생산에 널리 이용되는 중요한 생산 도구이다. 그러나 최근 다품종 소량생산의 확산에 따라 보다 효율적이고 경제적인 금형에 대한 요구가 증가하고 있으며, 본 연구에서는 금형 재료로서 초고강도 콘크리트의 적용 가능성을 모색해 보고자 한다. 초고강도 콘크리트는 80MPa 이상의 압축강도를 갖는 콘크리트로서 금속에 비해 저렴하고 무게가 가벼우며 조형이 용이하다는 장점을 가지고 있다. 초고강도 콘크리트가 비록 일반 금형 재료인 공구강에 비해 강도는 낮지만 상대적으로 낮은 응력이 발생하는 성형 공정에 사용된다면 금형 재료로서 충분히 활용 가능하다고 판단하였다. 따라서 본 연구에서는 플라스틱 저압 생산공정의 하나인 폴리우레탄 반응사출 성형공정용 시작 금형에 초고강도 콘크리트를 적용해 보았으며, 금형 제작 및 성형 과정을 통하여 금형 소재로서의 가능성과 특징을 고찰해 보았다.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2014년도 추계 학술논문 발표대회
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• pp.55-56
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• 2014

In this research, the effect of types of aggregate and SP on fundamental properties of ultra-high performance concrete of 80 MPa of compressive strength was evaluated to provide solution for high cost of ultra-high performance concrete. As the results of a series of tests, the mixture using limestone and silica aggregates showed improved workability rather than the mixture using granite aggregate. For compressive strength of UHPC, the UHPC mixtures using limestone and silica aggregates showed higher compressive strength than the UHPC mixture using granite aggregate while all mixtures satisfied target compressive range.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1994년도 가을 학술발표회 논문집
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• pp.157-160
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• 1994

Recently, many studies on the ultra high strength concrete are performed in our country. so, this study is aimed for analyzing the effects for replacement of silica fume and fly ash. As results, slump, slump flow and compressive strength is showed the high values in replacement silica fume. Tensile strength ratio is 1/17 and bending strength ratio is 1/6 for compressive, there are results of the test.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2005년도 봄학술 발표회 논문집(II)
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• pp.41-44
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• 2005

The aim of this study is to develop experimentally ultra high-strength concrete with compressive strength over 100MPa with current materials by important factors to influence the compressive strength of concrete. There are so many factors which influence the manufacturing of ultra high-strength concrete. But the experimental factors selected in this study are the sand aggregate ratio, the silica fume replacement ratio, the type of aggregate, the type of superplasticizer, the fiber mixing ratio. The results of this experimental study show that it is possible to applicate in the field.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2004년도 추계 학술발표회 제16권2호
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• pp.261-264
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• 2004

In this study, the experiment was carried out to investigate and analyze the strenth properties and flowability of ultra-high strength concrete accroding to types of mineral admixtures and cements. The main experimental variables were water/binder ratio $25.0\%$, water content $160kg/m^3$ and mineral admixtures such as fly ash, silica fume and meta kaolin. According to the test results, the principle conclusions are summarized as follows 1) In case of using admixtures, superplasticizer amount need more than plain concrete. 2) According to kinds of admixtures and cements, the viscosity of concrete show much difference. 3) The autogeneous shrinkage of ultra-high strength concrete is profitable that use admixture, and heat of hydration is desirable that apply considering countermeasure enough in the advance. 4) Meta kaolin is excellent in side but has viscosity enlargement efficiency a little. But, problem estimates that is not to make design strength to and $70N/mm^2$ if use mixing condition with water-binder ratio properly.