• 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.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2004년도 춘계 학술발표회 제16권1호
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• pp.200-203
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• 2004

In this study, it is examined the properties of flow and early strength of concrete according to superplasticizer. For this experiment, it is analyzed that the flow and strength properties according to the mixture factors, compared with naphthalene superplasticizer(normal & delay type) focused on polycarboxylate superplasticizer. (1) The slump loss of concrete used polycarboxylate superplasticizer showed $4\~8cm$, it is judged that slump loss according to the time lapse can be minimized. (2) The performance of polycarboxylate superplasticizer is about $70\%$ level of the normal naphthalene type, it is superior to the delay type, but the performance showed so lowly. The 28days, early strength didn't differ according to the kind of superplasticizer.

• 한국세라믹학회지
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• 제47권5호
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• pp.387-393
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• 2010

To improve concrete quality one of the most widely used chemical admixtures is polycarboxylate type superplasticizer. Unlike lignosulfonate and naphthalene-sulfonate, it has high dispersion property and excellent sustainable dispersion property for cement and concrete. Thus, polycarboxylate type superplasticizer has been widely used as a high-performance water reducing admixture together with silica fume in high-performance concrete and other applications for the dispersion of high-strength concrete over 100 MPa. However, even though there have been many studied on the dispersion of concrete by the structure of polycarboxylate type superplasticizer, there have a few studied that clarified the relationships between its rheological properties and microstructure properties in the early hydration behavior of ordinary portland cement. To investigate the correlations between the rheological properties and microstructure of cementitious materials with polycarboxylate type superplasticizer, this study experimented on the rheology, pore structure, heat evolution, and consistency in early hydration as well as on the compressive strength by early dispersion characteristics.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2005년도 추계 학술발표회 제17권2호
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• pp.671-674
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• 2005

In this study, it is examined the properties of early strength of concrete mixed with polycarboxylate superplasticizer. For this experiment, it is analyzed that the slump and strength properties according to the mixture factors, compared with cements and superplasticizers of each company and curing temperature($15,\;20^{\circ}C$). (1) The slump loss of concrete used polycarboxylate superplasticizer(rapid strength type) showed $0.5\~1.5cm$, it is judged that slump loss according to the time lapse can be minimized. (2) The performance of polycarboxylate superplasticizer kept up consistency and accelerated strength development. it is possible to reveal 12MPa within $18\~20$hours at $20^{\circ}C$ curing, but impossible within 24hours at $15^{\circ}C$. (3) It is necessary to studies about rapid strength development in the low temperature.

• 한국세라믹학회지
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• 제48권6호
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• pp.504-509
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• 2011

In this study, the effect of superplasticizers on the dispersibility and hydration properties of cement with silica fume were investigated. Superplasticizers are used Naphthalene type, Ligno-sulfate type and polycarboxylate type. Compared with plastic viscosity of cement paste without superplasticizers(Plain), plastic viscosity of cement paste with superplasticizers are reduced and yield stress of cement pastes with each superplasticizer is increased rather than Plain. And then, plastic viscosity of cement paste with Naphthalene type superplasticizer was the least of all types. Compared with other two types, setting and hydration of cement paste with Polycarboxylate type(PC) superplasticizer is very fast. At compressive strength after 3-day, PC is higher than other two types, But, compressive strength of after 7-day and 28-day, PC is smaller than other two types.

• 한국세라믹학회:학술대회논문집
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• 한국세라믹학회 2004년도 춘계총회 및 연구발표회 초록집
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• pp.52.1-52.1
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• 2004

• 한국건축시공학회지
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• 제22권5호
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• pp.441-450
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• 2022

본 연구에서는 순환자원으로 구성된 비소성 시멘트의 유동성 확보를 위해 감수제의 종류 및 첨가율에 따른 비소성 시멘트 모르타르의 유동성과 강도 특성을 분석하였다. 감수제 첨가에 따른 비소성 시멘트의 유동성은 감수제 첨가비율이 높고 플라이애시 치환 비율이 높을수록 유동성은 향상되는 것으로 나타났다. 특히 폴리카르본산계 감수제 첨가 시 소성 시멘트 모르타르보다 유동성 확보에 유리하며, 비소성 시멘트 모르타르의 적정 유동성 확보와 동시에 강도 확보가 가능한 것으로 판단된다. 또한 감수제 첨가에 따른 비소성 시멘트 모르타르는 고칼슘 애시의 치환 비율이 높고 염기도가 높을수록 반응성이 촉진되는 경향이 있는데 급격한 반응 촉진은 오히려 강도저하를 유발할 수 있으므로 목표한 유동성을 만족하는 범위 내에서 적정 배합조건을 도출하였다.

• 한국세라믹학회지
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• 제44권2호
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• pp.103-109
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• 2007

In this study, the rheological properties of cement pastes containing blastfurnace slag of different fineness were investigated. The fluidity of cement pastes with low Blaine value blastfurnace slag was increased with decreasing the plastic viscosity and the yield stress of pastes. And the optimum dosage of polycarboxylate type superplasticizer to the cement pastes was confirmed according to the fineness and the replacement ratio of blastfurnace slag. All cement pastes showed the thixotropy behavior. And also it was formed that the segregation range of cement pastes was occurred below $10D/cm^2$ of the yield stress and below 350 cPs of the plastic viscosity by the coaxial cylinder viscometer.

• 한국세라믹학회지
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• 제41권5호
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• pp.417-424
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• 2004

메톡시폴리에틸렌글리콜모노메타크릴레이트(MPEGMAA)와 메타크릴산(MAA)을 공중합시킨 폴리카복실레이트계 고유동화제(PCA)의 그라프트 사슬인 폴리에틸렌옥사이드(PEO)의 길이가 다를 경우, 보통포틀랜드시멘트(OPC)의 수화 반응에 미치는 영향을 Fourier Transform Infrared Spectroscopy(FT-IR), X-Ray Diffraction(XRD)과 Differential Scanning Calorimetry (DSC)를 이용하여 조사하였다. PCA의 그라프트 사슬의 길이에 따라 초기 재령에서 수화 반응에 미치는 영향은 달라지나, 장기 재령에서는 큰 차이가 없었다. 또한 PCA가 첨가된 경우의 Ca(OH)$_2$의 상대 피크 강도의 비(I[001］/I［101］)는 OPC에 비해 감소하였다.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2006년도 추계 학술발표회 논문집
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• pp.801-804
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• 2006

Polycarboxylate type superplasticizers(PC) have got widely used for making not only high performance concrete but low grade concrete as well. It is known that fluidity of cement with PC is affected by the characteristics of cement especially sulphate ion concentration and hydration activity. But the characteristics of PC also affect the fluidity. The fluidity of cement mortar with various types of PC was measured and critical dosage(CD) and dispersing ability(DA) was calculated. CD and DA is strongly dependent on the type of PC. And the variation of fluidity on time was affected by the type of PC also. So, it is advisable to investigate the property of PC before production of concrete and adjust it to meet the requirements of concrete depending on the materials, the time of transport and so on.