• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2002년도 봄 학술발표회 논문집
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• pp.551-556
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• 2002

High-performance concrete is defined as concrete that meets special combinations of performance and uniformity requirements that cannot always be achieved routinely using conventional constituents and normal mixing, placing, and curing practices. Ever since the term high-performance concrete was introduced into the industry, it had widely used in large-scale concrete construction that demands high-strength, high-flowability, and high-durability. To obtain such performances that cannot be obtained from conventional concrete and by the current method, a large number of trial mixes are required to select the desired combination of materials that meets special performance. In this paper, therefore, using genetic algorithm which is a global optimization technique modeled on biological evolutionary process-natural selection and natural genetics-and can be used to find a near optimal solution to a problem that may have many solutions, the new design method for high-performance concrete mixtures is suggested to reduce the number of trial mixtures with desired properties in the field test. Experimental and analytic investigations were carried out to develop the design method for high-performance concrete mixtures and to verify the proposed mix design.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1999년도 학회창립 10주년 기념 1999년도 가을 학술발표회 논문집
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• pp.263-266
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• 1999

This study aims to make high performance concrete for normal strength using crushed stone fines to control high strength of the high performance concrete. According to the experimental results, when crushed stone fines are increased every 10%, 15% of compressive strength is decreased, and 5% of drying shrinkage is increased, compared to normal high performance concrete. Also, high performance concrete has been evaluated to have good durability factor more than 100% in the 480cycle of freezing and thawing test, without regard to using AE and crushed stone fines.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1997년도 가을 학술발표회 논문집
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• pp.422-429
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• 1997

In recent years, concrete construction have become larger and higher and are demanding high performance concrete with lower heat to prevent thermal cracking, far greater workability, high strength and durability. Application of low heat portland(Type IV) cement for the high performance concrete is the best solution to satisfied those requirements. Here are explained the basic properties of fresh concrete as well as hardened concrete of high performance concrete using low that portland cement.

• Advances in concrete construction
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• 제1권2호
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• pp.151-162
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• 2013

The performance characteristics of high-strength and high-performance concrete are discussed in this review. Recent developments in the field of high-performance concrete marked a giant step forward in high-tech construction materials with enhanced durability, high compressive strength and high modulus of elasticity particularly for industrial applications. There is a growing awareness that specifications requiring high compressive strength make sense only when there are specific strength design advantages. HPC today employs blended cements that include silica fume, fly ash and ground granulated blast-furnace slag. In typical formulations, these cementitious materials can exceed 25% of the total cement by weight. Silica fume contributes to strength and durability; and fly ash and slag cement to better finish, decreased permeability, and increased resistance to chemical attack. The influences of various mineral admixtures such as fly ash, silica fume, micro silica, slag etc. on the performance of high-strength concrete are discussed.

• 한국건축시공학회지
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• 제2권4호
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• pp.163-168
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• 2002

The object of this study is to define the characteristics of high performance concrete with varing compressive strength of concrete and curing temperature. The major test variables are 1) high strength concrete(500kg/$cm^2$) and ordinary strength concrete(240kg/$cm^2$) compressive strength, 2) curing temperature and condition, 3) concrete curing age, 4) three types of cement. From the test results were shown that curing temperature and curing conditions were also very effective for high strength concrete and ordinary strength concrete, and concrete were largely effected by cement type and temperature during the hydration reaction process. This paper describes the effect of curing temperature for strength and characteristics of high performance concrete.

• Computers and Concrete
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• 제10권4호
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• pp.409-417
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• 2012

The quality of high performance concrete largely depends on water cement ratio, porosity, material composition and mix methods. The uniformity of color, texture and compressive strengths are quality indicators commonly used to assess the overall characteristics of concrete mixes. The homogeneity and share of coarse aggregates play a key role in concrete quality and must be analyzed in a microscopic point of view. This research studies the quality of high performance concrete by taking drilled cores in both horizontal and vertical directions from a 1.0 $m^3$ specimen. The coarse aggregate, expressed in digitized $100{\times}116$ dpi resolution images are processed based on brightness in colors through commercial software converted into text files. With the image converting to text format, the share of coarse aggregate is quantified leading to a satisfactory assessment of homogeneity - a quality index of high performance concrete. The compressive strengths of concrete and the shares of coarse aggregate of the samples are also compared in this research study to illustrate its correlation in concrete quality. It is concluded that a higher homogeneity of aggregate exists in the vertical plane than that of the horizontal planes of the high performance concrete. In addition, the concrete specimen showing denser particle packing has relatively higher compressive strengths. The research methodology provides an easy-to-use, direct measurement of high performance concrete when conducting quality assessment in the construction site.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2008년도 춘계 학술발표회 제20권1호
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• pp.1113-1116
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• 2008

실리카퓸, 플라이애쉬, 고로슬래등 미분말 혼화재가 포함된 고성능 콘크리트(High Performance Concrete) 교량 바닥판 보호공법은 1980년 초부터 북미를 중심으로 사용되어 왔다. 본 보고서에서는 교량 바닥판 보호를 위한 고성능 콘크리트 적용사례와 고성능 콘크리트를 이용한 두 가지 공법(고성능 콘크리트 교면포장공법, 노출 바닥판 공법)에 대해 소개한다. 위 두 공법은 이미 북미에서 많은 실적을 보유하고 있으며 특히, 실리카퓸과 PVA섬유가 포함된 고성능 콘크리트 교면포장공법은 국내에서도 성공적으로 적용되고 있다. 따라서 본고에서는 기존 아스팔트 재료를 대체할 수 있고, 최근 국내에서도 그 적용성에 대한 관심과 실 시공이 이루어지고 있는 고성능 콘크리트를 이용한 교면포장 (Overlay) 공법 및 노출 바닥판(Full depth) 공법에 대해 소개하고자 한다.

• KCI Concrete Journal
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• 제11권3호
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• pp.19-28
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• 1999

This study treated self-compacting high Performance concrete as two Phase materials of Paste and aggregates and examined the effect of powder and aggregates on self-compacting high performance, since fluidity and segregation resistance of fresh concrete are changed mainly by paste. To improve the fluidity and self-compactibility of concrete, optimum powder ratio of self-compacting high performance concrete using fly ash and blast-furnace slag as powders were calculated. This study was also designed to provide basic materials for suitable design of mix proportion by evaluating fluidity and compactibility by various volume ratios of fine aggregates, paste, and aggregates. As a result, the more fly ash was replaced, the more confined water ratio was reduced because of higher fluidity. The smallest confined water ratio was determined when 15% blast-furnace slag was replaced. The lowest confined water ratio was acquired when 20% fly ash and 15% blast-furnace slag were replaced together. The optimum fine aggregates ratio with the best compactibility was the fine aggregate ratio with the lowest percentage of void in mixing coarse aggregate and fine aggregate In mixing the high performance concrete. Self-compacting high performance concrete with desirable compactibility required more than minimum of unit volume weight. If the unit volume weight used was less than the minimum, concrete had seriously reduced compactibility.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2010년도 춘계 학술대회 제22권1호
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• pp.479-480
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• 2010

콘크리트 구조물의 고성능, 고내구성화를 위해 콘크리트 뿐만 아니라 보강 재료에 대한 성능 향상이 요구되고 있다. 본 연구에서는 고성능의 보강재료를 복합적으로 적용하여 고강도 콘크리트 구조물의 성능 극대화를 도모하는 하이브리드 보강기법에 대한 연구를 수행하였다.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1998년도 가을 학술발표논문집(II)
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• pp.501-506
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• 1998

This paper is an experimental study on the flexural strength and ductility capacity of reinforced high performance concrete beams with the concrete which has compressive strength of 600~700kg/$\textrm{cm}^2$, slump value of 20~25cm and slump-flow value of 60~70cm. Total 8 beams with different tensile reinforcement ratio and pattern of loading were tested. Form the results of reinforced high performance concrete beams, the equivalent stress block parameters proposed by MacGregor et al. or New Zealand code are recommended to use. Also, an extreme fiber concrete compressive strain of reinforced high performance concrete beams are distributed 0.0033~0.0048. In reinforced high performance concrete beams, reinforcement ratio in order to insure curvature ductility index 2 and 4 propose by ACI code should be less than those of reinforced normal strength concrete beams.