• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2001년도 학술논문발표회
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• pp.46-51
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• 2001

As a rule, in case of CFT for high-rise building, high strength concrete is required since it should have high fluidity, segregation resistance and large proportion of cement per unit considering the fi11ing beneath the diaphragm. However, regarding the low-rise building under 20 stories, it is somewhat difficult to use high strength concrete. This is a fundamental study to develop a concrete with normal strength and high fluidity for CFT of low-rise building, whose purposes are in speculating several kinds of changes in concrete's characteristics through various experiments and offering basic documents for practicalization in si to and production through mock-up test.

• 한국건설순환자원학회논문집
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• 제3권3호
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• pp.268-276
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• 2015

본 논문에서는 탄소저감을 위한 산업부산물 사용 증대 및 시공성능 향상을 위하여 시멘트 사용량을 80% 이상 감소시킨 탄소저감형 4성분계 고유동 콘크리트를 제조하여 품질특성, 및 탄소저감 성능을 수행하였다. 탄소저감형 4성분계 고유동 콘크리트의 품질특성 평가를 수행한 결과 다량의 산업부산물을 혼합하여 시멘트 사용량을 80% 이상 감소시킨 배합에서 목표 성능을 만족하는 품질을 얻을 수 있었으며, 유동특성, 역학특성 및 내구특성의 경우 기존 기준 배합과 비교하여 다소 성능이 감소되는 경향이 나타났지만 소요 성능 수준 이상의 성능을 만족할 수 있는 것으로 판단된다. 또한, 탄소저감형 다성분계 고유동 콘크리트의 탄소저감 성능을 분석하기 위하여 콘크리트의 전 과정 평가를(LCA) 실시한 결과 기존 기준 배합과 비교하여 약 62.2%의 탄소저감 성능이 있는 것으로 나타났으며, 제조비용의 경우 약 24.5%의 원가 절감이 되는 것으로 나타났다.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2008년도 추계 학술발표회 제20권2호
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• pp.813-816
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• 2008

본 연구에서는 시멘트페이스트의 유동성 및 수화반응속도에 미치는 폴리카르본산계 고성능AE감수제의 영향에 대해서 첨가율, 분자구조 등의 관점에서 검토를 하였다. 시멘트페이스트의 유동성은 폴리카르본산계 고성능AE감수제를 첨가하는 것에 따라 증가하였다. 또한 그래프트가 짧은 폴리카르본산계 고성능AE감수제를 사용한 경우가 그래프트가 긴 것에 비해 저첨가율에서의 유동성은 향상되었다. 시멘트페이스트의 최고수화발열속도까지의 도달시간에 미치는 폴리카르본산계 고성능AE감수제의 영향은 첨가율이 증가함에 따라 증가하였다. 더욱이 시멘트페이스트의 유동성이 동일할 정도의 첨가량에 있어서도 그래프트가 긴 폴리카르본산계 고성능AE감수제의 경우가 그래프트의 길이가 짧은것의 경우보다 최고수화발열속도까지의 도달시간에 미치는 영향은 작다는 것을 알 수 있었다.

• Advances in nano research
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• 제13권1호
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• pp.13-28
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• 2022

The pumpability of the grouts is significant issue in concept of the rheological and workability properties during penetrating to voids and cracks. To improve the fluidity features of the grout mixes, the usage of Colloidal Nano Particular Powders (CNPPs) with mineral additives such as fly ash (FA) can contribute. Therefore, the main purpose of this study can be explained as investigating the usage effects of four types of Colloidal Nano Particular Powders (n-TiO₂, n-ZnO, n-Al₂O₃ and n-SiO₂) as nano additives on the rheological, workability and bleeding properties of cement-based grout incorporated with fly as. Test results showed that the usage of FA in the grout samples positively contribute to increase on the fluidity of the grout samples as expected. The dilatant behavior was observed from the results for all mixes. Observing the effect of nano-sized additives in such cement-based grout mixtures with high fluidity has presented remarkable effects in this study.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2017년도 춘계 학술논문 발표대회
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• pp.212-213
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• 2017

The study investigated the fluidity and compressive strength of non-cement porous block using blast furnace slag powder to reduce CO₂ in the construction industry.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1998년도 가을 학술발표논문집(II)
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• pp.269-274
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• 1998

In this study, to increase fluidity and resistance of segregation of materials, the effect of each of the materials, which have effects on high performance concrete from investigating the properties of strength and drying shrinkage of high performance concrete made by the basic mix proportion used fly-ash and ground granulated blast-furnace slag after hardening, has been checked. According to the experimental results, fluidity on W/C = 34% was satisfied within slump-flow 65$\pm$ 5cm and U-type self-compactability difference 5cm. On the properties of strength, high performance concrete produced compressive strength over 400kg/$\textrm{cm}^2$ in 28days when powder was replaced by 40% of fly-ash and 60% of ground granulated blast-furnace slag. And compressive strength was taken over 600kg/$\textrm{cm}^2$ equal to non-replacement in 91days. Also, the length change of concrete with the addition of fly-ash was smaller than that without it. Therefore, it may be effective on the decrease of drying shrinkage volume.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1998년도 가을 학술발표논문집(II)
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• pp.275-280
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• 1998

In this study, to increase fluidity and resistance of segregation of materials, the effect of each of the materials, which have effects on high performance concrete from investigating the properties of strength and drying shrinkage of high performance concrete made by the basic mix proportion used fly-ash and ground granulated blast-furnace slag after hardening, has been checked. By the results of this experiment, fluidity on W/C=34% was satisfied within slump-flow 65$\pm$5cm and U-type self-compacting difference 5cm. On the properties of strength, high performance concrete produced compressive strength over 400kg/$\textrm{cm}^2$ in 28days when powder was replaced by 40% of fly-ash and 60% of ground granulated blast-furnace slag. And compressive strength was taken over 600kg/$\textrm{cm}^2$ equal to non-replacement in 91days. Also, the length change of concrete with the addition of fly-ash was smaller than that without it. Therefore, it may be effective on the decrease of drying shrinkage volume.

• 한국건축시공학회지
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• 제2권1호
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• pp.163-169
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• 2002

In this study, there are kind of property experiments like fluidity, compressive strength, bleeding measurement, concrete sink for CFT use high fluidity concrete. The property difference between before transmit and after transmit concrete in the mock up test with ready mixed concrete equipment is examined. The variable factors in mock up are diaphragm existence and nonexistence, diaphragm placing hole sizes. To investing the concrete Property under diaphragm, concrete packing ability, hydration heat, core specimen strength tests are performed.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2005년도 춘계 학술기술논문발표대회 논문집
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• pp.25-28
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• 2005

This study shows the early quality improvement of concrete with calcium sulfa aluminate(CSA). For the properties of slump, plain concrete incorporating BS $35\%$ and UP $15\%$ resulted in high fluidity compared with OPC without any admixture. As displacement ratio of CSA increased. the fluidity decreased. The fluidity also declined with setting time. Increase of incorporation ratio of CSA declined bleeding and accelerated setting time. Importantly, using more CSA helped to improve early compressive strength and decrease drying shrinkage. In term of water curing, drying shrinkage hardly ever occurred.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1998년도 가을 학술발표회 논문집(I)
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• pp.191-196
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• 1998

Under concentrational paste and dilute suspension systems, we have been tested the effects in the dosage of two superplasticizers [naphtalenic(NSF) and polycarboxylic(NT-2)] which has been varied from 0 to 2.0 wt%, in both one case of cement Ⅱ-anhydrite and fly ash itself and the other case that cement has been substituted 10wt% to Ⅱ-anhydrite and fly ash. The result of tested zeta potential tells that zeta potential values increase in addition to increasing of the NSF dosage. And it's effect was high in case of fly ash. We has confirmed the 10wt% substitution of Ⅱ -anhydrite and fly ash would be more effective than the cement itself in initial fluidity and stable fluidity. And in case of NT-2 and NSF, addition of 1.0wt% NT-2 improved the fluidity of paste cement more than that for NSF.