• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2022년도 가을 학술논문 발표대회
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• pp.25-26
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• 2022

The purpose of this study is to prevent serious disasters in cold weather by presenting an optimal blending design for securing high early strength when placing concrete by analyzing the properties and compressive strength of concrete formulations using high early strength admixture materials.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2001년도 가을 학술발표회 논문집
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• pp.669-674
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• 2001

Electric Arc Furnace Dust (EAF Dust) Is residual dust produced during the manufacturing of metal products from heavily heated electric arc furnace. Many researches have focused on recycling and reusing EAF Dust for industrial and construction purposes. However, most of these researches were aimed at obtaining useful heavy metal powders by treating toxic metallic materials in EAF Dust. Also, few researches dealt with using EAF Dust as admixture in concrete mixture (i.e., slag dust). In this study, EAF Dust is used as admixture in concrete mixture content considering economical feasibility and construction applicability. The concrete specimens mixed with EAF Dust is then tested in compression and tension to study its strength and ductility as well as its failure mechanism. The compression and tension (by split cylinder test) test results are compared to the results from the specimens without EAF Dust to understand the chemical stability and mechanical characteristic of concrete specimens with EAF Dust. For the experiment, 6 types of admixture added concrete were studied: ⑴Combination of EAF Dust and blast-furnace slag in 1 to 1 ratio, ⑵Combination of EAF Dust and blast-furnace slag in 1 to 2 ratio, ⑶EAF Dust only, ⑷blast-furnace slag only, ⑸fly ash only, and ⑹no admixture. The experimental results show that the strength of EAF Dust added specimen has lower early age strength but higher 28 day strength when compared to other specimens. Also, the Elastic Modulus of EAF Dust is higher(28 days) than other specimens. The study results prove that EAF Dust can be used as an effective admixture in concrete for specific usages.

• 한국결정성장학회지
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• 제19권3호
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• pp.135-143
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• 2009

$Cr^{6+}$의 고용화 가능성과 lignin계 혼화제의 성능을 조사하기 위하여 과잉의 $Cr^{6+}$을 첨가하여 KSLI, 미국 TCLP법, Soaking Procedure를 이용하여 각 기준에 따른 용출 특성을 조사하였다. 그 결과 lignin계 혼화제는 첨가에 따라 모르타르 강도 증진을 보였으며 용출 특성에 큰 변화는 없었다.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2016년도 춘계 학술논문 발표대회
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• pp.151-152
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• 2016

In this study, the shrinkage properties of concrete with the high-performance shrinkage admixture and the crack reinforcing materials applied to the high-flatness flooring of hypermarkets, outlets and warehouses was evaluated. The concrete with the popular shrinkage admixture is significantly reduced compared to the plain concrete without shrinkage admixture for the dry shrinkage deformation, and the difference of shrinkage ratio between the concretes has been shown to increase with increasing age.

• 한국건축시공학회지
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• 제6권4호
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• pp.93-98
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• 2006

Admixture materials are used in mixing concrete or mortar to improve quality and performance of the concrete. This study examines the potential use of talc as a substitute for cement, the benefits of recycling waste resources for economical efficiency and quality improvement of concrete. The test was carried out by replacing the plain mix with fine grains of talc at the rate of 10%, 20%, and 30%. Talc was divided into three groups depending on the degree of pulverizing. For wet concrete, porosity, slump, bleeding per unit, and setting time by penetration resistance were measured; similarly, for dry concrete, strength and watertight Property were tested. Test results showed that the amount of bleeding and setting time could be shortened, but the strength and watertight proofing severely deteriorated. However, at the replacement rate of 10%, talc showed equal performance with the plain at all degrees of pulverization, which suggests its potential use as admixture material.

• 한국도로학회논문집
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• 제15권5호
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• pp.101-110
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• 2013

PURPOSES : The purpose of this study is to evaluate the durability of ternary blended concrete mixtures adding ultra fine admixture. METHODS : From the literature review, crack was considered as the main distress failure criterion on concrete bridge deck pavement. To reduce the initial crack development due to drying shrinkage, CSA expansion agent and shrink reduction agent were used to ternary blended concrete mixtures as a admixture. Laboratory tests including chloride ion penetration test, surface scaling test, rapid freeze & thaw resistance test, non restrained drying shrinkage and restrained drying shrinkage test were conducted to verify the durability of ternary blended concrete mixtures. RESULTS : Based on the test results, proposed mixtures were verified as high qualified durable materials. Expecially initial drying shrinkage crack was not occurred in ternary blended concrete mixtures with CSA expansion agent. CONCLUSIONS : It is concluded that the durability of proposed ternary blend concrete mixture was acceptable to apply for the concrete bridge deck pavement.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2001년도 The 6th International Symposium of East Asian Resources Recycling Technology
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• pp.549-554
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• 2001

The authors have proposed that waste glass, which is crushed to pieces, can be used as a concrete aggregate. At the present time, recycled-glass concrete is used for sidewalk concrete blocks and pavement as glass is ornamental. However, in cases where recycled-glass concrete is used for structural concrete, strength and durability are required as structural concrete is exposed to the weather. Glass that is used generally is a mixture of SiO$_2$, Na$_2$O and CaO. SiO$_2$is the most likely cause of alkali-aggregate reaction when waste glass was used for concrete aggregate. In this study, an alkali-aggregate reaction test that is one of the important tests related to durability of aggregate was carried out far discussion of utilization of waste glass for concrete aggregate. From the results of the tests, it is found that glass is a reactive aggregate. The pessimum proportion of glass is about 75%. Then the cases of using fly ash, blast furnace slag and artificial zeolite for admixture materials were also examined for the purpose of prevention of alkali-aggregate reaction. from the results of the test, it was found that using them is an effective way to prevent alkali-aggregate reaction. The compressive strength in the cases of using admixture materials is larger than that without admixture materials.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2008년도 춘계 학술발표회 제20권1호
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• pp.881-884
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• 2008

현재 국내에서 많은 양의 도자기 폐기물이 발생하고 있으며, 이들 폐기물은 경제적 이득과 환경보전의 차원에서 재활용하는 방안이 모색되어져야 한다. 따라서, 본 연구에서는 도자기 폐기물을 시멘트 혼합재로 이용하여 폐도자기의 재활용성을 검증하고자 하였다. 실험 결과 시멘트 혼합재로 사용된 폐도자기분말이 5%, 7%까지 PHC파일의 압축강도에 영향을 주었으며, 폐도자기분말을 시멘트 혼합재로 사용하여 PHC파일의 강도를 개선시킬 수 있었다.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2004년도 추계 학술발표회 제16권2호
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• pp.297-300
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• 2004

The purpose of this study reutilization of waste fine tailing as admixture for cement. We observe tailing's basic properties such as shape, physical and chemical basic features. Also, various admixtures were made of 2 Types of tailings, OPC, fly-ash and blast furnace slag. The basic properties of the cement mortars incorporation with these admixtures were examined and analyzed under a verity of experimental conditions. This work showed that the tailing separated coarse materials could be effectively utilized as replacement materials of cement without any decrease in the strength if we can control the blaine of materials like OPC, slag and fly ash.

• 한국결정성장학회지
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• 제33권2호
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• pp.54-60
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• 2023

본 연구에서는 탈황석고(DG)에 이산화탄소를 반응시켜 만든 탄산화물(CCMs)의 시멘트 혼합재로서 적용 가능성 분석을 위해 탈황석고와 탄산화물의 미세구조 및 기초물성 분석을 실시하였다. 탈황석고의 경우 CaO 및 CaSO₄가, 탄산화물의 경우 CaSO₄, CaCO₃, Ca(OH)₂ 및 CaSO₄·H₂O 결정상이 주 결정상으로 나타났으며 입도분석 결과 두 재료의 평균 입자 크기의 차이는 약 7 ㎛로 나타났다. 또한 탄산화물은 폐기물공정시험기준에 따른 중금속 용출시험 결과 주요 중금속이 불검출되었으며 열중량 분석 결과 탈황석고에 비해 CO₂ 분해가 2배 이상 나타난 것으로 보아 설비 운전 조건 최적화를 통해 건설 소재 원료로 활용 가능할 것이라 판단된다. 탈황석고와 탄산화물의 함량별 강도 거동 측정 결과 탄산화물 혼입 모르타르의 장기강도가 더 높은 것으로 나타났으며 이는 탄산화물에 존재하는 CaCO₃의 충전제 효과 때문인 것으로 나타났다.