• 한국안전학회지
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• 제16권1호
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• pp.65-72
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• 2001

Portland cement concrete is made with coarse aggregate, fine aggregate, portland cement, water and, in some cases, selected chemical admixture such as air-entraining agents, water reducer, superplasticizer, and so on, and mineral admixture such as fly ash, silica fume, slags, etc. Typically, in the concrete, the coarse aggregate and fine aggregate will occupy approximately 80 percent of the total volume of the finished mixture. Therefore, the coarse and fine aggregates affect to the properties of the portland cement concrete. As the deposits of natural sands have slowly been depleted, it has become necessary and economical to produce crushed sand(manufactured fine aggregate). It is reported that crushed sand differs from natural sands in gradation, particle shape and texture, and that the content of micro fines in the crushed sand affect to the quality of the portland cement concrete. Therefore, the purpose of this paper is to investigate the characteristics of fresh and hardened concrete with higher micro fines. This study provides a firm data to apply crushed sand with higher micro fines.

• 한국농공학회:학술대회논문집
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• 한국농공학회 2003년도 학술발표논문집
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• pp.411-414
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• 2003

This study is performed to examine the physical and mechanical properties of recycled polymer concrete using recycled coarse aggregate and recycled fine aggregate. Tests for compressive strength, flexural strength and pulse velocity with replacement ratio of recycled coarse aggregate and recycled fine aggregate are performed. As a result, compressive strength, flexural strength and pulse velocity of polymer concrete containing recycled coarse aggregate are in the range of $826{\sim}849kgf/cm^2,\;192{\sim}200kgf/cm^2\;and\;3,932{\sim}4,000m/s$, respectively. Compressive strength, flexural strength and pulse velocity of polymer concrete containing crushed stone only are $805kgf/cm^2,\;197kgf/cm^2$ and 3,931 m/s, respectively. Accordingly, recycled aggregates is expected that can be utilizing as an aggregate of polymer concrete.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2006년도 춘계 학술발표회 논문집(II)
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• pp.161-164
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• 2006

The main objective of this study was to evaluated the physical properties of concrete with substitution ratio of recycled fine aggregate and recycled coarse aggregate made of waste concrete. The replacement ratios of recycled coarse and fine aggregate decided 0%, 30%, 40% and 50% respectively to get the deregulate of floor space Index. The test result showed that compression strength of cylinder mold decrease with the substitution ratio increase but its strength of replaced recycled fine aggregate higher than OPC.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2000년도 봄 학술발표회 논문집
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• pp.521-526
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• 2000

The structural behavior of the members using recycled coarse aggregate is investigated in this papers. The members considered this study are subjected to shear ad bending simultaneously. A series of test beam specimens using recycled coarse aggregate is made for the structural test. These specimens are manufactured using the concrete for the compressive strength of 280kg/$\textrm{cm}^2$ with recycled aggregate ratio of 0%, 20%, 40%, 60%, 80% of total aggregate volume, respectively. The main object of this test is to investigate the influence of the using recycled aggregate to the cracking strength of the member subjected to flexure and shear and the post cracking behavior.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2004년도 추계 학술발표회 제16권2호
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• pp.205-208
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• 2004

The purpose of this study is to recycle waste concrete and reuse reclaimed asphalt concrete as a concrete coarse aggregate. In this experiment, recycled coarse aggregate was substitute for natural crushed aggregate at the rate of 0, 30, $50\%$, and reclaimed asphalt concrete was substitute for recycled coarse aggregate at the rate of 0, 10, 20, $30\%$. According to the experimental results, as the reclaimed asphalt concrete content has influence on the properties of recycled aggregate concrete such as compressive and tensile strength, the criteria for the substitute ratio should be required to be set.

• 한국농공학회:학술대회논문집
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• 한국농공학회 2002년도 학술발표회 발표논문집
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• pp.161-164
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• 2002

This study was performed to find out the regression function to calculate the modulus of elasticity of concrete mixed by river coarse aggregate. The distribution of the group of core strength made a normal curve and the effect factor in the modulus of elasticity was 0.97 at the concrete compounded by river coarse aggregate.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1990년도 가을 학술발표회 논문집
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• pp.113-116
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• 1990

This study is designed to analyze the variation of grading and shape of aggregate with the number of rotations of Los-Angeles abrasion machine, and is aimed to analyze the effect of slump and compressive strength of strength of concrete with the shape of coarse aggregate by the abrasion act.

• 한국건축시공학회지
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• 제19권4호
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• pp.313-322
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• 2019

본 연구는 최근 사용량이 증대하고 있는 저시멘트 배합을 대상으로 국내생산 인공경량 잔 굵은골재의 혼합비율에 따른 경량콘크리트의 물성 및 강도특성을 비교 검토한 것으로서 실험결과, 프리웨팅 시간이 24시간 증가할 경우 모르타르 플로우값이 약 3~5% 감소하는 것으로 나타났으며 경량잔골재 사용에 의해 모르타르 배합에서 약 10.4%의 기건단위질량 감소효과를 얻을 수 있는 것으로 나타났다. 또한 경량굵은골재의 혼합비율에 따른 경량콘크리트의 기건단위질량은 5~10mm 크기인 LWG10 경량굵은골재의 혼합비율이 높아질수록 선형적으로 기건단위질량이 증가하였으며 LWG10 경량굵은골재를 혼합할 경우 LWG10 혼합비율에 관계없이 재령 7일에 약 30~31MPa 수준의 유사한 압축강도를 발현하였다.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2002년도 가을 학술발표회 논문집
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• pp.579-584
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• 2002

In this research, the physical properties of self compacting concrete using ground granulated blast furnace slag as a part of cement were investigated. Concrete using ground granulated blast furnace slag was prepared with various ground granulated blast furnace slag replacement(20~80 volume %) for cement and the quantities of coarse aggregate in concrete were 50%, 55% and 60% of ratio of absolute volume of coarse aggregate. The workability, flowing characteristics, air content and compressive strength of concrete using ground granulated blast furnace slag were tested and the results were compared with those of ordinary portland cement concrete. In the experiment, we acquired satisfactory results at the point of flowing characteristics and strengths of concrete using ground granulated blast furnace slag within tile replacement ratio of 50% and the optimum quantity of coarse aggregate in concrete was found to be 50%~55% of ratio of absolute volume of coarse aggregate.

• 한국농공학회논문집
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• 제48권7호
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• pp.25-31
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• 2006

Permeable polymer concretes can be applied to roads, sidewalks, river embankment, drain pipes, conduits, retaining walls, yards, parking lots, plazas, interlocking blocks, etc. This study was to explore a possibility of using bottom ash as filler and recycled coarse aggregate of industrial by-products for permeable polymer concrete. The tests carried out at $20{\pm}1^{\circ}C$ and $60{\pm}2%$ relative humidity. At 7 days of curing, unit weight, void ratio, compressive and flexural strength and coefficient of permeability ranged between $1,652{\sim}1,828kgf/m^{3},\;15{\sim}29+%,\;18.2{\sim}24.5\;MPa,\;6.4{\sim}8.4\;MPa\;and\;6.8{\times}10^{-2}{\sim}1.7{\times}10^{-1}\;cm/s$, respectively. It was concluded that the bottom ash and recycled coarse .aggregate can be used in the permeable polymer concrete.