• Journal of the Korea Institute of Building Construction
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• v.5 no.1 s.15
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• pp.123-129
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• 2005

This study is as a part of the new disposal and recycling plans of heat-resource waste of Daegu dyeing industrial center we tried to examine applicable possibility of crushed thing(waste aggregate) as aggregates for mortar and concrete. To examine applicable possibility of waste aggregate as a lightweight-aggregate for concrete and mortar, we carried this study by mainly property examination of concrete according to replacement ratio of waste aggregate. We carried slump, unit weight, compressive strength and bending strength test according to replacement ratio of waste aggregate. As the result of that, if we use waste aggregate, lightweight of concrete and mortar will be possible. Specially it shows a strength improvement effect of cement hardening according to using this so it is judged that applicable possibility as aggregate for concrete and mortar is very excellent.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2012.11a
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• pp.81-82
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• 2012

The purpose of this study is the hydration properties of motar using Blast-Furnace Slag(BFS) with water elured from recycled coarse aggregate. The results of the experiment show that the water eluted from recycled coarse aggregate mixed with blast furnace slag has comparatively higher hydration activity than the mortar not mixed with one in early-age mortar causing the calcium hydroxide in the recycled coarse aggregate to work on as a stimulus to the hydration of ground granulated blast furnace slag. BFS mixed with the eluting water the hydration reaction was a promotion.

• Journal of Industrial Technology
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• v.24 no.A
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• pp.173-178
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• 2004

It is the purpose of this study to identify comprehensive fatigue characteristics of pavement concretes considering coarse aggregate types. The types of coarse aggregates considered are limestone, sandstone and granite, which are the most representative stones in Korea. The static strength tests were carried out to check the compressive strength, flexural strength at 7 and 28 days, and split tension strength at 56 day in order to minimize the various effect of strength during the test. The results are follows. The comprehensive fatigue models of pavement concretes were developed considering coarse aggregate types. The developed model showed a good relationship between aggregate types. The fatigue models with coarse aggregate types were shown, respectively. The combined fatigue models was also shown.

• Proceedings of the Korea Concrete Institute Conference
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• 2006.05b
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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.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2014.05a
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• pp.270-271
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• 2014

In this study, a replacement ratio of blast furnace slag coarse aggregate and a water binder ratio by an optimum combination of PHC file was investigated. As a results, the target strength 78.5MPa was altogether satisfied in a mix proportion 28-G100-SG0 and W/B ratio 26 %. The surface rupture was generated in 28-G0-SG100 combination after curing with the autoclave. According to the result of measuring the ingredient, the majority were the MgOH2 hydrate.

• Proceedings of the Korea Concrete Institute Conference
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• 2003.11a
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• pp.102-105
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• 2003

The purpose of this study is to examine the influence of the flowability and the compressive strength of concrete after the improving of grain shape of the coarse aggregate and fine aggregate fineness modulus. According to the experimental results, the coarse aggregate after improvement of grain shape it lead to be down by 6% fine aggregate ratio, from 47% to 41%. The 0.5% increase of fine aggregate fineness modulus lead to 3% increase of concrete slump, and 1% reduction of concrete air content. While compressive strength on fine aggregate fineness modulus, it was increased until fineness modulus 3.0, but after it reached by 3.5 it was decreased. The compressive strength of the coarse aggregate after improving the grain shape was decreased by 6% due to loss of the adhesion of cement paste.

• Magazine of the Korea Concrete Institute
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• v.10 no.1
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• pp.119-124
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• 1998

콘크리트는 시멘트, 잔골재 및 굵은 골재, 물 및 첨가제의 양이나 투입순서 ,혼합방법등 여러 가지 요인에 따라 성질이 바뀌게 되는 복합재료이다. 따라서 넓은 의미에서 품질 판정의 한 수단이 되는 콘크리트의 설계기준강도 또는 압축강도 fc'(=28일 압축강도)는 물론 기타의 성질도 정확한 예측이 불가능하다. 즉 소요강도를 목표로 배합된 공시체의 시험결과는 예외없이 통계적 가변성을 나타낸다. 여기에서는 공시체의 7일 강도의 평균치 및 표준 편차와 공시체의 28일 강도 측정치로부터 콘크리트의 압축강도를 추정하는식을 제안하였다. 이를 위하여 7,320개의 강도시험자료를 수집한 후 이들을 선형 회귀 분석법으로 처리하였다. 제안된 식에 의한 콘크리트의 압축강도는 타 추정식에 의한 값보다 실측치에 좀 더 근접함을 보여주었다. 또한 제안식의 검정을 위해 서울지역 자료 5,200개를 수집하여 제안식과 JIS, Slater식과의 오차를 비교한 결과에 따르면 제안식이 더 안전측임을 알 수 있었다. 그리고 슈미트 햄머에 의한 현장 실측 강도와 제안식과의 콘크리트 강도 오차는 대체로 2.3%이었다.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.3 no.1
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• pp.53-64
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• 1983

It was investigated by experimental method whether fine powder and coarse particle obtained by briquet cinders crushing could be used in the place of cement and fine aggregate or coarse aggregate for concrete. Except these experiments, further study, containing the fundamental physical properties of briquet cinders and the mechanical properties of concrete using briquet cinders, is needed for practical use, but these experimental results suggest the possibility for using briquet cinders as materials for mortar or concrete.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2018.05a
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• pp.218-219
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• 2018

This study analyzed the unit weight and compressive strength properties of lightweight concrete using high volume blast furnace slag powder by the mixing ratio of lightweight coarse aggregate to investigate the properties of lightweight concrete using domestic artificial lightweight aggregate.

• Proceedings of the Korea Concrete Institute Conference
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• 2005.05b
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• pp.513-516
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• 2005

Previous study on recycled aggregate(RA) has largely been limited to the manufacture of nonstructural-grade concrete due to undesirable physical properties of them such as, high water absorption leading to high water demand of concrete. The restriction seriously limits its market and consequently diminishes the use of RA as a construction material. This paper presents the mechanical properties of recycled concrete substituted by both waste foundry sand(WFS) and recycled coarse aggregate replaced with fine and coarse aggregate concurrently. The result shows that the compressive and tensile strength decrease with the increment of substitution ratio of RA and WFS while bending strength of RA concrete increase.