• 대한토목학회논문집
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• 제8권3호
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• pp.43-52
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• 1988

국산 플라이애쉬를 혼합한 콘크리트의 혼합률, 물결합재비와 재령과 강도와의 관계 및 워커빌리티에 대하여 실험을 통하여 검토하였다. 아울러 플라이애쉬를 사용한 콘크리트의 배합방법 3 종류에 대해서도 비교 고찰한 결과, 국산 플라이애쉬의 품질을 평가하는데 유익한 참고자료를 얻었다.

• 한국세라믹학회지
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• 제36권7호
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• pp.725-733
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• 1999

It is a fundamental experiment to use blast-furnace slag in solidification/stabilization process. The compressive strength and leaching test of Pb and Cr doped samples were evaluated and the effects of heavy-metal ions on the hydration of slag was investigated. Sodium silicates(5wt%) was added as alkali-activator and the effects of replacing a part of slag with flyash or gypsum was also discussed. Pb ion was solidified by encapsulation of matrix. In of slag${\pm}$gypsum binder microstructure was densified by accelerating to form AFt/AFm phase and compressive strength was improved resulting in reducing leaching amount of Pb ion. Cr ion was solidified by substituting with Al ion in aluminate product. Slag+fly ash binder improved compressive strength and decreased leaching amount of Cr ion.

• 한국세라믹학회지
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• 제35권12호
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• pp.1280-1285
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• 1998

Foaming method is presented the preparation of porous materials from high-concentrated kaolin silica and flyash slurries. The slurries were foamed dried and sintered respectively. The porosity of sintered ma-terials was about 70-75% Mean pore-size was the range of 70-150$\mu\textrm{m}$ and pore structure was continuous Sodium lauryl sulfate anionic surfactant was used as a foaming agent. The foaming ability and the froth sta-bility were increased with increasing the concentration of the foaming agent. But the size of the constituent bubble of froth after foaming process was not affected by the concentration of the foaming agent. These results showed that the mean pore-size of sintered materials was closely related to the froth stability which is related to the change of bubble-size during the drying process.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2005년도 봄학술 발표회 논문집(II)
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• pp.177-180
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• 2005

Decing agent with chloride promote frost damage of concrete structure in winter period. From the safetyside, however, it is difficult to stop using chloride. Therefore, the durable concrete is required from now on. In this paper, long-term freezing and thawing test was carried out using the freezing water containing $CaCl_{2}$ to consider the concrete scaling according to the kind of binders, such as OPC, Flyash, Slag+Fa. and Slag As a result, it was found that the degree of scaling is different with containing slag being considered to prevent the penetration chloride ion and according to each binders.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 1997년도 Lecture Notes by Two Distinguished Scholars
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• pp.1.1-16
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• 1997

This lecture summarizes the progress of the development of the different ground improvement techniques in Bangkok Plain and is reviewed in relation to the extensive deep wen pumping and the resulting piezometric drawdown at deeper depths. Case records of test embankments with sand drains, sand wicks and PVD are presented to inustrate the effectiveness of different types of vertical drains with surcharge. The use of prefsbicated drain seems more superior than the other types of sand drain. Construction of test embaxlkment, criteria for PVD selection and relevant laboratory testing techniques are discussed for formulating the specif'ication. Alternative teckuuque, such in, the use of deep chemical mixing is reviewed in terms of the efficiency of cement, lime and flyash as additive. Vacuum pre-loading with surcharge and elctro- osmotic consolidation are also explored as possible tectmiques to improve the engineering properties of soft Bangkok clay.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2006년도 추계 학술논문 발표대회 논문집
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• pp.43-46
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• 2006

The Hwangtoh is one of the traditional construction material used in wall, plastering material, and ondol (Korean underfloor heating system) with stone and wood. It is an important greenness material and it has much advantages such as; high storage of heat, auto-purification, antibiotic ability, and emission of far infrared rays. But, it is not developed and not used in modern construction because of its low strength and properties of dry shrinkage crack. According to the recent researches and studies, it is evaluated for natural pozzolanic material like flyash or pozzolan. It's possibility on construction material is high because it's chemical and mineralogical proportion is like as Metakaolin and Kaolinite. In this point of view, this study aims to analyze the physical properties on Hwangtoh mortar through an experiment with various activation condition of Hwangtoh, which is natural pozzolanic material, for the purpose of increase the using possibility in construction material.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2004년도 추계 학술발표회 제16권2호
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• pp.739-742
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• 2004

In this study, it was founded to make the optimal mixture for producing concrete which is self-compacting, yet, and generates low heat of hydration by using flyash, blast furnace slags and limestone powders as binders in addition to cement while using super-plasticizers and viscosity agents as admixture agents. The structural behaviors of the concrete produced with the selected mixture were compared with those of the concrete currently using for construction of nuclear power plants. The study shows that the blended high fluidity concrete including limestone is better in workability and durability than the concrete currently in use for nuclear power plants.

• 한국세라믹학회지
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• 제35권11호
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• pp.1227-1232
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• 1998

In order to prohibit the delay of early stage hydration activator Na2SO4 was added to Fly Ash blended ce-ment and its effects were investigated. Various measurements such as Compressive strength Heat of hy-dration Pore size distribution Hydration products Microstructure were evaluated and the results show that specimens of Fly Ash(50wt%) with 5% Na2SO4 dramatically improved the compressive strength because pozzolanic reaction of Fly Ash and the formation of ettringite make th microstructure denser than OPC and flyash cement paste.

• 한국지반공학회논문집
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• 제15권2호
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• pp.43-71
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• 1999

본 연구는 하수처리장 슬러지를 사용하여 매립지의 복토재 및 차수재의 건설재료로 개발하기 위하여 수행한 실험의 분석결과이다. 하수슬러지에 그의 지반공학적 물성증진을 위하여 화강토와 화력발전소의 부산물인 플라이애쉬를 주첨가물로 사용하고 부첨가물로 시멘트 및 벤토나이트를 소정의 혼합비율로 섞어서 각각 전단강도 증진과 투수계수 감소효과를 도모하였다. 주재료인 하수슬러지와 첨가재의 혼합비율을 변화시킨 혼합물에 대하여 다양한 실내실험을 수행하여 복토재 및 차수재의 설계기준의 적합성 여부를 조사하였다. 각 주재료, 첨가재, 혼합물의 비중, 입도분석, 액\ulcorner소성한계 실험을 실시하여 기본물성을 구하고 그들이 투수성, 다짐성, 압축성, 전단강도에 미치는 영향에 대하여 분석하였다. 혼합물에 대하여 실내다짐시험을 실시하여 최대건조단위중량과 최적함수비를 구하고 현장 다짐효율성을 평가하였다. 다짐혼합시료에 대하여 변수두 투수시험을 실시하여 투수계수를 구하는 한편 변수두 투수시험을 하중제어식 압밀시험중에 병행 실시하여 그들의 압밀정수 및 투수계수를 측정하였다. 슬러지의 장기적 안정성과 관련하여 크리프실험을 변수두 투수시험과 함께 실시하였다. 한편, 한달간을 부패시킨 다짐시료에 대하여 투수시험을 실시하여 슬러지내 유기물질 부패에 의한 투수계수에 미치는 영향에 대하여 고찰하였다. 슬러지에 화강토, 플라이애쉬, 벤토나이트를 일정비율로 섞은 혼합물에 대하여 직접전단시험을 실시하여 전단강도정수를 구하였다. 시멘트와 혼합한 슬러지에 대하여 일축압축 강도시험을 실시하여 혼합비와 재령기간에 따른 압축강도 변화를 분석하였다. 한편, 다짐혼합시료에 대하여 CBR시험을 수행하여 그들의 주행성에 대한 평가를 실시하였다. 이와 같은 다양한 실험결과를 종합분석하여 매립지의 차수재 및 복토재로서 사용조건 만족여부를 검토하였다.

• 한국건설순환자원학회논문집
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• 제6권3호
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• pp.207-213
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• 2018

최근 환경오염물질의 배출을 감소시킬 수 있는 순환유동층 보일러가 화력발전시설로서 점차 많이 사용되고 있다. 그러나 순환유동층보일러에서 발생하는 플라이 애시는 낮은 $SiO_2$와 상대적으로 높은 MgO와 $SO_3$ 함유량을 갖고 있으며, 또한 플라이 애시에 포함된 free CaO는 시멘트의 초기팽창 또는 급격한 초기응결을 발생시킬 수 있는 위험이 있다. 따라서 기존의 미분탄연소 (PCC) 플라이 애시와 순환유동층(CFBC) 플래이애시를 콘크리트분야에서 같이 활용할 수 있도록 KSL5405가 개정 발표되었다. 본 연구에서는 PCC와 CFBC 플라이 애시를 사용한 혼합시멘트를 제조하여 화학적성질과 역학적 성질을 분석하였다. CFBC 플라이 애시만을 혼합된 시멘트의 경우에는 OPC와 비교하여 강도는 낮아지는 반면, 높은 경시변화 특성을 나타내었으나, PCC와 CFBC를 혼합한 시멘트의 경우에는 PCC 플라이 애시만을 사용한 경우와 비교하여 강도가 높은 것으로 분석되었다. 실험결과로부터 CFBC 플라이 애시는 재료안전성과 요구되는 재료성능을 확보하기 위해 PCC와 같이 사용하여야 하는 것으로 판단된다.