• 한국도로학회논문집
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• 제14권5호
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• pp.67-74
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• 2012

PURPOSES: In this study the influence factors related to abrasion resistance of interlocking concrete block have been evaluated, and comparisons between various domestic and foreign abrasion test methods was also accomplished. METHODS: The modified rotational cutting method suggested in ASTM C 944 was applied. Surface materials with different types of fine aggregate such as crushed sand, sea sand, and mixture of crushed and sea sand were tested to compare the aggregate effect for abrasion resistance. RESULTS: The different surface mixtures with various W/C ratios, mortar and fly ash ratios have been investigated for functional and economical considerations. CONCLUSIONS: This study had obtained reliable results by changing diamond blade of rotating cutter. Therefore, in order to improve the abrasion resistance of interlocking concrete block for road, a new mix design was proposed.

• 한국건설순환자원학회논문집
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• 제2권2호
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• pp.76-82
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• 2006

High-strength, High-durability concrete appearance was embossed by benevolence who quality for each raw material that become factor that is direct in concrete manufacture and the special quality is very important and request properties of matter were also strengthened more. Specially, natural resources of good quality were abundant past in occasion of aggregate and unlike concrete request strength past that the importance was less relatively the quality enemy than cement because is also not big, importance of aggregate quality great veried as concrete strength and request properties of matter about durability are strengthened more on extreme displacement. Mixing four who is original and mixs special quality examination of domestic three Four-Stick Games by Chaechwiwon and age Four-Stick Games and crushed sand examined concrete quality characteristic that use mortar and concrete quality characteristic, special quality of North Korea sun guardian mountain three Four-Stick Games that is imported from the North Korea, North Korea sun guardian mountain three Four-Stick Games etc..

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2015년도 춘계 학술논문 발표대회
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• pp.71-72
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• 2015

As this study is the one related to the ultra high strength concrete essentially used for high rise buildings, it has analyzed on the flowability of ultra high strength concrete according to the variation of coarse aggregate and fine aggregate. The coarse aggregate was planned as two types including Granite Aggregate (GA) and crushed coarse Limestone Aggregate (LA) while fine aggregate was planned as four types including Sea Sand (SS), Limestone Crushed Fine Aggregates (LFA), Electric Arc Furnace Oxidizing Slag Aggregates (EFA) and Crushed Sand (CS) to perform experiment with a total of eight variables. As a result of analyzing slump flow, 500mm concentration time, U-Box and L-Flow, etc. among the characteristics of fresh concrete, a mix using LA+LFA is determined to show high flowability in case of applying ultra high strength concrete.

• 한국농공학회논문집
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• 제48권4호
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• pp.23-30
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• 2006

This study is performed to evaluate flowability of high flowable concrete using ordinary portland cement, crushed coarse aggregate, crushed sand, sea sand, fly ash, lime powder and superplasticizer. The slump flow and air content are increased with increasing the content of lime powder. But, the O-type funneling time and Box-type passing are decreased with increasing the content of lime powder. The slump flow, air content, O-type funneling time, Box-type passing and L-type filling of target compressive strength 21-27 MPa and 35-42 MPa at curing age 28 days are 47-50 cm and 56-60 cm, 4.2-5.5% and 4.0-5.7%, 8-12s and 5-10s, 4.3-5.0 cm and 3.4-5.0 cm, and excellent, respectively. These concrete can be used for high flowable concrete.

• 한국농공학회논문집
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• 제55권3호
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• pp.123-128
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• 2013

This study was performed to evaluate the slump flow, air content, setting time, compressive strength, adiabatic temperature rise and diffusion coefficient of chloride used ordinary portland cement, crushed coarse aggregate, crushed sand, river sand, fly ash, limestone powder, blast furnace slag powder and superplasticizer to find optimum mix design of low carbon green concrete for structures. The performances of low carbon green concrete used fly ash, limestone powder and blast furnace slag powder were remarkably improved. This fact is expected to have economical effects in the manufacture of low carbon green concrete for structures. Accordingly, the fly ash, limestone powder and blast furnace slag powder can be used for low carbon green concrete material.

• 한국안전학회지
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• 제14권1호
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• pp.124-128
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• 1999

Product background of cement, sand and coarse aggregate differ from country to country, so that thermal behaviour of concrete make a difference in high temperature. To cope with demand, this paper is a study on compressive strength for W/C 45%, 55% and 65% by using domestic portland cement, Han-river sand, sea sand and crushed-coarse aggregate. As a result, it is shown that it is estimating to the mechanical properties of heated concrete specimens under various W/C ratio.

• Structural Engineering and Mechanics
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• 제53권6호
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• pp.1241-1251
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• 2015

Faced with the growing needs of material resources and requirements of environmental protection for achieving sustainable development, it has become necessary to study and investigate all possibilities of exploring crushed and dune sand, reusing industrial wastes and by-product, and also applying new technologies including sand concrete which can replace the conventional concretes in certain structures to surmount the deficit on construction materials, conserve natural resources, lessen the burden of pollutants to protect the environment and reduce the consumption of energy sources. This experimental study is a part of development and valorization of local materials project in Skikda region (East of Algeria). It aims at studying the effects of partial replacement of sand with marble waste as fines on several fresh and hardened properties of sand concrete in order to reuse these wastes in the concrete manufacturing, resolve the environmental problems caused by them and find another source of construction materials. To achieve these objectives, an experimental program has been carried out; it was consisted to incorporate different percentages of marble waste fines (2, 4, 6, 8, 10 and 12%) in the formulations of sand concrete and study the development of several mechanical and rheological properties. We are also trying to find the optimal percentage of marble waste fine replaced in sand concrete that makes the strength of the concrete maximum. Obtained results showed that marble waste fines improve the properties of sand concrete and can be used as an additive material in sand concrete formulation.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2001년도 봄 학술발표회 논문집
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• pp.501-506
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• 2001

An experimental study was carried out to investigate recycling of an oyster shell, which is disposed in open-dumped way at coastal oyster factory area. For this purpose, the chemical component and reaction of oyster shell with cement paste was examined. And, the characteristics of hardened concrete was quantitatively investigated in terms of fineness modulus and blending rate of the crushed oyster shell. Test results show that interaction between oyster shell and cement paste was not occurred and the crushed oyster shell can be used as the fine aggregate of concrete. And it is found that blending of an oyster shell caused not to reduce the 28 day compressive strength of concrete. Elastic modulus of the concrete blended with crushed oyster shells decreases with increases the blending rate which the modulus reduced about 10% when oyster shells is blended up to the 20% of the sand substitution.

• 한국농공학회논문집
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• 제55권6호
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• pp.11-17
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• 2013

This study was performed to evaluate the chlorine ion penetration resistance, chemical resistance and freezing and thawing resistance used ordinary portland cement, crushed coarse aggregate, crushed sand, river sand, fly ash, limestone powder, blast furance slag powder and superplasticizer to find optimum mix design of low carbon green concrete for structures. The performance of low carbon green concrete used fly ash, limestone powder and blast furnace slag powder were remarkably improved. This fact is expected to have economical effects in the manufacture of low carbon green concrete for offshore structures. Accordingly, the fly ash, limestone powder and blast furnace slag powder can be used for offshore structure materials.

• 한국산학기술학회논문지
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• 제13권8호
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• pp.3719-3725
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• 2012

최근, 건설공사의 급증으로 인한 양질의 하천모래의 고갈로, 콘크리트용 대체골재로서 바다모래, 부순모래 및 순환잔골재 등의 사용이 증가하고 있다. 그러나, 미세척 바다모래는 함유된 염화물로 인하여 철근콘크리트 구조물에 사용할 경우, 철근부식 유발로 구조물의 내구성에 악영향을 미치고, 부순모래는 미립분이 많고 입도조정이 어려워서 철근콘크리트 구조물에 널리 사용되지 못하고 있는 실정이다. 한편, 낙동강 세사는 낙동강 중 하류에 대규모로 분포하고 있고, 입도를 제외하면 콘크리트용 잔골재로서 품질이 우수하므로 이에 관한 연구가 시급히 요구되고 있다. 따라서 본 연구의 목적은 콘크리트 잔골재로서 낙동강 세사를 적극적으로 활용하기 위하여 그것의 물성을 평가하는 것이다. 이를 위하여 낙동강 본류 대표위치별로 시료를 채취하여 이들의 절건밀도, 입도, 단위용적질량 등의 물성을 평가하였는데, 그 결과 낙동강 세사는 입도를 제외하면 잔골재로서의 물성이 우수한 것으로 나타났다.