• 콘크리트학회논문집
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• 제12권4호
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• pp.49-58
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• 2000

There are many methods to improve the performance of concrete. Especially, granuated blast furnace slag. by-products used in concrete as the replacement material of cement, could contribute to improve the fluidity, resistance of chemical attack and strength of concrete. Also, it could contribute to decrease the rate of generating hydration heat, in addition to cost-down of concrete and prevention of enviromental pollution. Therefore, in order to establish the systemical application of granuated blast furnace slag in normal concrete, the engineering properties of concrete, such as fluidity, strength, setting and hydration properties etc.. was evaluated. In this study, replacement ratio of granuated blast furnace slag was 0, 30, 50, 70(%), and target slump was 8, 12, 15, 18(cm). Results from the experiment, granuated blast furnace slag showed the outstanding effects of improving the engineering properties of concrete. From now on, positive application of granuated blast furnace slag is expected in the point of improving the performance and cost-down of concrete.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2019년도 춘계 학술논문 발표대회
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• pp.36-37
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• 2019

In domestic construction industry progress, construction and quality control of large structures are considered to be important as the superstructure and mass scale of structures. In the case of mass concrete, high hydration heat caused by cement hydration generates temperature stress by generating internal temperature difference with the concrete surface. These temperature stresses cause cracks to penetrate the concrete structure. A method of lowering the heat generation by incorporating Urea in order to reduce the concrete temperature crack has been proposed. In this study, the heat function coefficient for the FEM temperature crack analysis of the mass concrete containing the element was derived and the adiabatic temperature rise test was carried out according to the incorporation of the element. As a result of this experiment, the maximum temperature of 41 ± 1℃ was obtained irrespective of the amount of urea, and the maximum temperature decreased by 16.9℃ in concrete containing 40kg/㎥ of urea.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1998년도 봄 학술발표회 논문집(I)
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• pp.155-160
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• 1998

In this study, the estimation method of adiabatic temperature rise of concrete was developed by using hydration heat generation of mineral compounds of clinker and pozzolans. Specific heat considered the effects of mix proportion and temperature was calculated with experimental data. The adiabatic temperature rise calculated by developed method were compared with experiments in which many types of cement and admixtures were used. As the results of this study, it was found that the developed method could calculate adiabatic temperature rise of concrete accurately without the experiment.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2010년도 춘계 학술대회 제22권1호
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• pp.259-260
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• 2010

본 연구는 저발열 콘크리트의 적용성 검토를 위한 기초적 시험으로서, 각각의 배합조건 및 규격별 물리적 성질 및 수화열 저감특성을 알아보고자 하였다.

• 한국응용과학기술학회지
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• 제27권2호
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• pp.175-182
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• 2010

Various research on the surface of the skin and the relationship between epidermis and composition of ion have been performed. Traditionally, bamboo extract was used as an important material for enhancing healthy condition of a skin. Bamboo salt is well known as one of the most famous traditional medical treatments. In this study, we investigated the stability of P/S (Polyol-in-Silicone) emulsions containing a fair amount of bamboo salt in the range of 0.5~5.0 wt%. For improving the stability of emulsions, we varied the quantity of fatty alcohol and wax ester in emulsions and the stability was checked using DSC (Differential Scanning Calorimeter). We also studied the efficacy of treating the P/S emulsions containing bamboo salt. From the experiment, the emulsions show the mitigation of stimuli, enhancing the skin hydration and improving the appearance of the skin.

• 한국재료학회지
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• 제23권12호
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• pp.687-694
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• 2013

This study was performed with an aim to improve the early-age strength of concrete containing fly ash, which is known to increase the long-age strength of concrete, reduce drying shrinkage, and enhance water tightness. The composition was partially substituted with calcium sulfoaluminate (CSA), from which ettringite is actively produced, in the early stages of hydration to verify its effect on improving the early-age strength and to determine the optimal mixing ratio. For this purpose, up to 30 % of the cement weight was substituted with fly ash, and the amount of CSA substitution was 8% of the fly ash weight. The mixtures were then fabricated into concrete specimens for compressive strength measurement and analysis of the correlation between the hydration products and the compressive strength.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2003년도 학술.기술논문발표회
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• pp.81-87
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• 2003

The purpose of this study is the development of a recycling process to recover the hydrated ability of cement hydrate which accounts for a large proportion of cementitious powder by concrete waste in order to recycle cementitious powder by concrete waste as recycle cement. Therefore, after having theoretical consideration based on the properties of high-heated concrete, we consider the properties of hydration of cementitious powder in hardened mortar under various temperature conditions. As a result of experiment, it is revealed that an effective development of recycling cement is possible since the cementitious powder by concrete waste recovers a hydraulic property during burning at $600^{\circ}C$ or $700^{\circ}C$. And it is shown that the fluidity of mortar decreases rapidly as the burning temperature of recycle cement increases. however, the improved effect of fluidity is predominant if adding the additive such as fly-ash or blast furnace slag.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2004년도 추계 학술발표회 제16권2호
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• pp.289-292
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• 2004

This study was performed to know effective control of crack occurred by hydration heat, restraint of multiplication of hydration heat, through mechanical test, strength test and crack control test using fluosilicate salt based anti-crack agent made from by-product during phosphoric acid manufacturing process. Mix proportions for experiment were modulated at 0.495 of water to cement ratio and addition amount of fluosilicate salt based anti-crack agent to $1.0\%$. Condensation time was late and compressive strength of hardened concrete cured at several days was executed to evaluate characteristics of crack control for concrete. It is ascertained that characteristics of crack control for concrete could be improved by an adequate addition of fluosilicate salt based anti-crack agent.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2023년도 가을학술발표대회논문집
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• pp.35-36
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• 2023

In this study, the hydration characteristics of conductive grout materials for each binder were investigated using XRD, and as a result of the experiment, the specimen with UFFA consumed more Ca(OH)₂ than the specimen with other binders, which is judged to have activated the pozzolanic reaction of UFFA, a high powder.

• 한국건설순환자원학회논문집
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• 제2권3호
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• pp.217-224
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• 2014

본 연구에서는 Premixed 혼합시멘트를 사용한 저발열 콘크리트에 대하여 기초물성 평가로 공기량, 슬럼프 및 압축강도 시험을 수행하고, 수화열 해석을 수행하여 Premixed 혼합시멘트를 사용한 콘크리트의 현장 적용성을 검토하였다. 검토 결과 Premixed 혼합시멘트를 사용한 저발열 콘크리트는 목표 작업성 및 설계기준 압축강도를 충분히 만족하였다. 또한, 수화열 해석 결과 Premixed 혼합시멘트를 사용한 저발열 콘크리트는 목표 온도균열지수를 충분히 확보할 수 있었다. 따라서, 현장 교량구조물의 교각 기초-기둥의 시공에 있어 Premixed 혼합시멘트를 사용한 저발열 콘크리트의 적용은 바람직한 것으로 판단된다.