• 한국구조물진단유지관리공학회 논문집
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• 제8권2호
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• pp.177-183
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• 2004

적산온도은 시멘트 수화의 결과로서 시간이 경과함에 따라 콘크리트 강도가 얻어진다는 것으로 콘크리트의 강도는 시멘트의 수화반응과 관계가 있다. 시멘트의 수화반응은 온도와 경과시간에 큰 영향을 받는다. 따라서 본 연구에서는 콘크리트 강도예측에 있어서 양생시간과 온도의 함수인 적산온도와 고강도콘크리트 강도의 상관성을 검토하고자 하였다.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2015년도 춘계 학술논문 발표대회
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• pp.48-49
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• 2015

High-calcium fly ash (FH) is widely used as mineral admixtures in concrete industry. In this paper, a hydration model is proposed to describe the hydration of high-calcium fly ash blended-cement. This model takes into account the hydration reaction of cement, the chemical reaction of fly ash, and reaction of free CaO in fly ash. Using the proposed model, the development of compressive strength of FH blended concrete is predicted using the amount of calcium silicate hydrate (CSH). The agreement between simulation and experimental results proves that the new model is quite effective.

• 한국세라믹학회지
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• 제24권3호
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• pp.289-295
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• 1987

The changes of physical properties of portland cement pastes and mortars were investigated by addition of sodium gluconate. Flow table experiment and viscosity measurement were took in order to find dispersing effect, and time-dependent changesof viscosity and rates of hydration heat evolution were carried out for the sake of finding retardation effect of hydration. And changes of physical properties of cement pastes and mortars were discussed by setting time, compressive strength and porosity.

• 한국세라믹학회지
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• 제19권1호
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• pp.19-23
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• 1982

The technique to determine the components in the supersulphated slag cement is discussed by several selective extraction analyses. Accordingly, the rate of hydration reaction of supersulphated slag cement could be quantitatively measured by the following 3 kinds of the selective extraction analyses. (1) Determination of unreacted slag - a salicylic acid, acetone.methanol solution (2) Determination of free $CaSO_4$ - a half saturated lime water (3) Determination of free $Ca(OH)_2$ - glycerine.alcohol solution

• 한국농공학회논문집
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• 제50권2호
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• pp.27-34
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• 2008

Recently, owing to the development of industry and improvement of building techniques, concrete structures are becoming larger and higher. This study was performed to analyze hydration reation properties of concrete with binders and admixtures, such as OPC, low heat cement, belite rich cement, slag powder, lime powder and fly ash. To investigate effects of PC type superplasticizer on the hydration, experiments involving FT-IR, XRD, DSC, SEM were analyzed at the curing age 1day, 3days and 28days. The hydration reaction rate of OPC concrete slightly delayed at the curing age 1day, blast furnace slag powder and fly ash were more effective. BRC and LHC concretes can be used for concrete structures in winter season.

• 한국재료학회지
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• 제22권11호
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• pp.598-603
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• 2012

MgO based cement for the low-temperature calcination of magnesite required less energy and emitted less $CO_2$ than the manufacturing of Portland cements. Furthermore, adding reactive MgO to Portland-pozzolan cement can improve their performance and also increase their capacity to absorb atmospheric $CO_2$. In this study, the basic research for magnesia cement using $MgCO_3$ and magnesium silicate ore (serpentine) as starting materials was carried out. In order to increase the hydration activity, $MgCO_3$ and serpentinite were fired at a temperature higher than $600^{\circ}C$. In the case of $MgCO_3$ as starting material, hydration activity was highest at $700^{\circ}C$ firing temperature; this $MgCO_3$ was completely transformed to MgO after firing. After the hydration reaction with water, MgO was totally transformed to $Mg(OH)_2$ as hydration product. In the case of using only $MgCO_3$, compressive strength was 35 $kgf/cm^2$ after 28 days. The addition of silica fume and $Mg(OH)_2$ led to an enhancements of the compressive strength to 55 $kgf/cm^2$ and 50 $kgf/cm^2$, respectively. Serpentine led to an up to 20% increase in the compressive strength; however, addition of this material beyond 20% led to a decrease of the compressive strength. When we added $MgCl_2$, the compressive strength tends to increase.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2002년도 가을 학술발표회 논문집
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• pp.369-374
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• 2002

In this paper, setting and hydration heat development characteristics with three binder types, type IV cement＋fly ash, type IV cement＋slag powder and type IV cement ＋ limestone powder. were investigate. As results, it was shown that the limestone powder decreased the initial setting time regardless of replacement ratio, especially the range of 20~50% replacement ratio, and the 2nd peak was shifted ahead when the limestone powder replacement ratio increased. But for the f1y ash and the limestone powder, contrary results were obtained compared with the limestone powder.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1998년도 가을 학술발표회 논문집(I)
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• pp.19-24
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• 1998

In this study, blended cement with low blaine(2000, 3000$\textrm{cm}^2$/g) blast-furnace slag power by 10-70wt.% was investigated through the measurement hydration heat, physical properties. The experiment results indicated compressive strength was decreased as low blaine slag blended, but hydration heat was reduced significantly and flow of the cement paste was increased.

• 콘크리트학회논문집
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• 제27권1호
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• pp.3-9
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• 2015

본 연구에서는 소량 혼합재로서 석회석과 고로슬래그를 단독 또는 복합으로 10%까지 혼합하면서 나타나는 보통 포틀랜드 시멘트의 수화특성에 대해 고찰하였다. 응결시간은 석회석과 고로슬래그를 복합하여 10% 혼합한 경우, 석회석의 혼합량이 증가할수록 Alite의 수화반응을 촉진시켜 종결이 빨라졌다. 재령 3일에서 모르타르의 압축강도는 석회석 5%-고로슬래그 5% 혼합이 가장 컸다. 이러한 이유로는 석회석에 의한 Alite의 수화촉진에 의해 생성된 C-S-H 수화물과 Alite의 수화촉진에 의해 부가적으로 생성된 $Ca(OH)_2$가 일부 고로슬래그와 반응하여 추가적으로 C-S-H 수화물을 생성하였기 때문이다. 재령 7, 28일에서는 석회석 3%-고로슬래그 7%의 복합 혼합이 가장 큰 압축강도를 나타냈다. 이 시기에는 고로슬래그의 수화반응이 활발한 시기로 C-S-H 수화물 생성량은 석회석의 혼합량보다 고로슬래그의 혼합량에 의존한다. 그리고 고로슬래그의 수화반응을 활성화하기 위해서는 $Ca(OH)_2$ 생성량이 증가해야 하므로, Alite의 수화를 활성화 시키는 소량의 석회석이 필요하다. 따라서 재령 7일 이후에는 고로슬래그의 혼합량이 많고 석회석의 혼합량이 적은 것이 보통 포틀랜드 시멘트의 강도발현에 효과적이었다.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2022년도 봄 학술논문 발표대회
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• pp.21-22
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• 2022

In order to improve the strength degradation of the cement-based material to which strong alkaline liquid red mud was added, the liquid red mud was neutralized with sulfuric acid and added to the cement paste to examine the mechanical properties according to the amount added. As a result of measuring the compressive strength, the strength was higher when the red mud was neutralized with sulfuric acid and added to the cement paste than the cement paste to which the liquid red mud was added. As a result of hydration heat measurement, when red mud was neutralized with sulfuric acid and added to the cement paste, an initial strength higher than that of liquid red mud was expressed.