• 시멘트
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• 통권62호
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• pp.49-55
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• 1976

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2023년도 봄 학술논문 발표대회
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• pp.43-44
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• 2023

This study evaluated the mechanical and electrical properties of low-cement mortar using a large amount of industrial by-products to reduce carbon emissions from the cement industry. As types of industrial by-products, blast furnace slag and fly ash, which are representative materials, were used, and ultra-high fly ash was mixed and evaluated to solve the problem of initial strength loss. In addition, in order to evaluate the electrical properties, 1% of MWCNT was incorporated relative to the powder mass. As experimental items, the compressive strength was measured on the 1st, 3rd, 7th and 28th days of age, and the rate of change in electrical resistance was measured on the 28th day of age. As a result of the experiment, the initial strength of the test specimen mixed with blast furnace slag and fly ash was significantly lower than that of 100% cement, and the specimen mixed with blast furnace slag showed strength equal to that of cement at 28 days of age. As an electrical characteristic, the electrical resistance was reduced when the load was loaded, and this reason is judged to be the effect of improving the conductivity as the connection between CNTs is narrowed by the compressive load.

• 콘크리트학회논문집
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• 제12권3호
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• pp.11-19
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• 2000

It has been reported that few manufacturers of cement mortar for precast products use chemical and mineral admixture due to the absense of restrictions related to the application of admixture and the poor manufacturing facilities. Therefore, this paper is intended to contribute to the improvement of quality by investigating the properties of cement mortar for precast products using fly ash, blast furnace slag and AE water reducing agent. According to the test results. it was found that the cement mortar products using fly ash and AE water-reducing agent had better qualities than those of ordinary portland cement.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2018년도 추계 학술논문 발표대회
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• pp.83-84
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• 2018

As the concentration of greenhouse gases in the atmosphere increases, the reduction of CO2 is gaining worldwide attention. In the construction industry, cement replacement materials such as fly ash and blast furnace slag were investigated to reduce CO2 emissions in cement production process. Precast concrete is used in the field after manufacturing in the factory in the form of pipes and bricks because of shortening construction period and cutting construction cost. According to the results of previous research, it is known that early CO2 curing in concrete using OPC or fly ash has an initial strength enhancement effect and can be used for precast concrete production. Therefore, the purpose of this study is to evaluate the strength improvement effect by confirming the initial strength improvement effect when blast furnace slag is mixed.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2023년도 봄 학술논문 발표대회
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• pp.297-298
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• 2023

In the concrete industry, efforts are being made to reduce CO₂ emissions, and technologies that collect, store, and utilize CO₂ have recently been studied. This study analyzed the change in compressive strength after the accelerated carbonation test of Non-Sintered Cement(NSC) mortar. Type C Fly Ash and Type F Fly Ash were mixed in a 1:1 ratio and then mixed with Blast Furnace Slag fine powder to produce NSC. The mortar produced was cured underwater until the target age. In addition, an accelerated carbonation test was conducted under the condition of a concentration of 5 (±1.0%) of CO₂ gas for 14 days. The mortar compressive strength was measured before and after 14 days of accelerated carbonation test based on the 7th and 28th days of age. As a result of the experiment, the compressive strength was improved in all binder. In general, the compressive strength of NSC mortar subjected to the accelerated carbonation test was similar to that of Ordinary Portland Cement(OPC) mortar not subjected to the accelerated carbonation test.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1997년도 봄 학술발표회 논문집
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• pp.124-128
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• 1997

In order tohave a betterunderstanding of thefavorable effect ofground granulated blast-furnace slag and fly ash, slump loss, temperature risingand compressive strength of concrete were investigated into diffrent conditions. When slag was mixed with ordinary portland cement as30%, slump loss gotto some 18% at 60min, maximum temperatureto some $43^{\cire}C$ at 180min, compressive strength similar to that of ordinary portland concrete at 28 days. Therefore it wasnoted thatslump loss andmaximum teaperaturerising of concrete were very reduced according to ground granulated blast-furnace slag and fly ash mixed with ordinary portland cement.

• 시멘트 심포지엄
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• 28호
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• pp.47-53
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• 2001

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2023년도 가을학술발표대회논문집
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• pp.195-196
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• 2023

Recently, the importance of eco-friendly and sustainable development has been emphasized. The construction industry also needs to make efforts to reduce cement use, which accounts for 8% of greenhouse gas emissions. This study examined the fluidity and compressive strength of a cementless composite using fine blast furnace slag powder and fly ash without using cement in order to reduce greenhouse gas emissions due to the use of cement.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2004년도 춘계 학술발표회 제16권1호
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• pp.584-587
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• 2004

This research investigates the rheological behavior and the confined water ratio of the cement paste and binder condition in order to predict mix design proportion of the high flowing concrete. The purpose of this study is to determine the optimum replacement ratio of binders including fly ash, and lime stone powder by the cement weight. For this purpose, belite cement, blast furnace slag cement and ordinary portland cement are selected. As test results, the confined water ratio shows the following range ; OPC>blast furnace slag cement>belite cement. Therefore, belite cement is proved very excellent cementitious materials in a view point of the flowability. The optimum replacement ratio of lime stone powder is shown over $30\%$ in case of belite cement and about $10\%$ in case of slag cement type. Also, the optimum replacement ratio of fly ash is shown $30\%$ by the cement weight considering the confined water ratio and deformable coefficient of the paste condition.

• 토지주택연구
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• 제3권3호
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• pp.287-297
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• 2012

보통포틀랜드시멘트(OPC)와 고로슬래그 및 플라이애시 만으로 설계기준압축강도 80MPa의 3성분계 고강도콘크리트(이하 고강도콘크리트)를 개발하기 위하여, 고로슬래그와 플라이애시의 대체율이 고강도콘크리트의 경화전 후 재료물성 변화에 미치는 영향을 평가하였다. 고강도콘크리트의 경화전후 재료물성 평가결과, 고로슬래그와 플라이애시 대체율이 최대 30%까지 증가할수록 유동성과 장기강도가 우수한 것으로 나타났다. 또한 OPC만으로 제작된 시험체와 비교하여 길이변화 특성이 우수하며, 혼화재 사용에 따른 탄산화는 없는 것으로 나타났다. 고강도콘크리트 재료물성 평가결과, 고로슬래그 대체율 25%, 플라이애시 대체율 15%일 경우, 경화전 후 재료물성이 가장 우수한 것으로 나타났다. 이 연구결과는 향후 고가의 실리카퓸을 대체할 수 있는 고강도콘크리트의 개발에 유용하게 활용될 수 있을 것으로 기대된다.