• 제목/요약/키워드: low-heat portland cement

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포틀랜드계 시멘트 콘크리트의 촉진 염화물 확산 특성 (Accelerated Chloride Diffusion Properties of Portland Cement Concrete)

  • 김진철;이찬영;이용은
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 1999년도 학회창립 10주년 기념 1999년도 가을 학술발표회 논문집
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    • pp.775-778
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    • 1999
  • Accelerated chloride diffusion tests were carried out to estimate the chloride diffusion coefficient of concrete using ordinary portland cement, low heat belite-rich portland cement, and sulphate resistant portland cement. Concrete using low heat belite-rich portland cement showed a high diffusion coefficient due to delayed hydration of low heat belite rich portland cement, while the diffusion coefficients of concrete using sulphate resistant portland cement and ordinary portland cement were low.

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골재의 온도 변화에 따른 저발열 포틀랜드 시멘트 콘크리트의 특성 (Properties of Low Heat Portland Cement Concrete by Changing Temperature of Aggregate)

  • 조용진;박광수;신수균;원종필
    • 한국농공학회논문집
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    • 제46권4호
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    • pp.49-55
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    • 2004
  • Properties of concrete using low heat portland cement is different from using ordinary portland cement and temperature of aggregate can be expected to have an important influence on its properties. In this study, experiment by setting up 5 levels (40, 30, 20, 4, $-2^{\circ}C$) by temperature of aggregate for evaluation properties of concrete using low heat portland cement was conducted. The experiments include slump test, air content test, change of slump, change of air content and compressive strength of concrete test. As the result of experiments, slump and air content was decreased by increasing temperature of aggregate. But it was not exceeding it's limit. Change of slump and air content was rapidly decrease by decreasing temperature of aggregate. At early age, compressive strength was influenced by the temperature of aggregate.

저열 포틀랜드(4종)시멘트를 사용한 고유동, 고강도콘크리트에 관한 연구 (A Study on the Properties of High Performance Concrete Using Low Heat Portland(Type IV) Cement)

  • 최광일;김기수;하재담;김동석;이순기;이동윤
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 1997년도 가을 학술발표회 논문집
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    • pp.422-429
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    • 1997
  • In recent years, concrete construction have become larger and higher and are demanding high performance concrete with lower heat to prevent thermal cracking, far greater workability, high strength and durability. Application of low heat portland(Type IV) cement for the high performance concrete is the best solution to satisfied those requirements. Here are explained the basic properties of fresh concrete as well as hardened concrete of high performance concrete using low that portland cement.

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저열 포틀랜드 시멘트 콘크리트의 고강도 영역에서의 강도발현 특성 (Strength Development of Low Heat Portland Cement Concrete in High Strength Range)

  • 하재담;엄태선;이종열;권영호
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 2005년도 봄학술 발표회 논문집(II)
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    • pp.353-356
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    • 2005
  • Strength development of low heat portland cement(Type IV) concrete in high strength range is tested. In this study strength development according to water-binder ratio, strength development according to age, effect of fly ash and super plasticizer are tested. This study tests effect of low heat portland cement in high strength range concrete and provide guide line concrete mix design for later study and/or construction.

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포틀랜드시멘트계 경화체의 황산염저항성 (Sulfate Resistance of Portland CementMatrices)

  • 문한영;이승태;김홍삼
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 2000년도 봄 학술발표회 논문집
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    • pp.714-717
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    • 2000
  • To consider sulfate resistance of cement pastes and motars for 3 types of portland cements which have different $C_3A$ contents an silicate ratio($C_3S/C_2S$), they were immersed in 5% sodium sulfate solution for 400 days. SEM analysis and ($Ca(OH)_2$ contents of cement pastes, and compressive strength and length change of cement mortars, were performed to investigate the effects of ($C_3$ and ($Ca(OH)_2$ contents. According to the results of this study, low heat portland cement pastes, and compressive strength and length change of cement mortars, were performed to investigate the effects of C3A and ($Ca(OH)_2$ contents. According to the results of this study, low heat portland cement had a good sulfate resistances because of a small quantity of gypsum and ettringite due to less ($Ca(OH)_2$ contents. However, ordinary portland cement had an adverse result. This was also confirmed by SEM analysis.

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저열 포틀랜드 시멘트 적용을 통한 SRC 교각 온도균열 제어 (Thermal Crack Control of SRC Pier Using Low-Heat Portland Cement)

  • 김태홍;하재담;유재상;이종열
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 2001년도 가을 학술발표회 논문집
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    • pp.297-302
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    • 2001
  • SRC pier at KTE 6-1 construction area is a very important structure. Precise control of quality is needed. This pier has 3.50m$\times$3.73m section and 38.20m length. So this structure must be treated as mass concrete and thermal crack caused by hydration heat should be controled. In this project belite cement concrete is used to control the thermal crack. As a result of adapting belite cement concrete perfect control is achieved. Finally, hydration heat FEM analysis of horizontal element is executed for Ordinary Portland Cement concrete and belite cement concrete. In comparison of two results, it is confirmed that using low heat portland cement concrete is necessary.

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비탄산염 원료 활용 저열시멘트 콘크리트 물성 평가를 위한 OPC와 저열시멘트의 물성 비교에 관한 연구 (A Study on the Comparison of Physical Properties of OPC and Low-Heat Cement for the Evaluation of Concrete Properties of Low-Heat Cement Using Non-Carbonate Raw Materials)

  • 권민수;허종완
    • 시멘트 심포지엄
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    • 통권49호
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    • pp.31-32
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    • 2022
  • 본 연구는 비탄산염 순환자원을 원료로 활용하여 석회석 사용량을 최소화할 수 있는 저열 시멘트 제조기술 개발을 위하여 일반 포틀랜드 시멘트(OPC)와 시중의 저열 포틀랜드 시멘트(LHC)의 물성을 비교하여 차이를 분석하기 위하여 모르타르를 배합비에 차이를 두고, 슬럼프, 강도, 내구성, 단열 특성 등의 물성평가를 실시하여 검토를 진행하고 있다.

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저열 포틀랜드(벨라이트)시멘트 콘크리트의 특성 (Properties of Low Heat Portland(Belite Rich) Cement Concrete)

  • 하재담;김기수;김동석;구본창;조계홍;이동윤
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 1998년도 가을 학술발표회 논문집(I)
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    • pp.66-71
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    • 1998
  • Recently, it has been increased to construct massive concrete structures, like under-ground structure, offshore structure etc., ie. concrete construction have become larger and higher and are demanding lower heat concrete to prevent thermal cracking. It has been progressed to replace cements with fly-ash and slag to lower heat of hydration, but it is hard to control quality of the mineral admixtures in stage of adjusting of real construction. Application of low heat portland(Belite Rich) cement for the mass concrete is the best solution to satisfied those requirements. Here are explained the basic properties of fresh concrete as well as hardened concrete of using low heat portland cement(LHPC). Also, we compare the results of adiabatic temperature rise test using LHPC and OPC.

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중국과 한국 시멘트의 품질규정에 대한 비교 연구 (A Comparison Study on Quality Regulation of China and Korea Cement)

  • 배장춘;김호림;이백수;한천구
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2006년도 춘계학술논문 발표대회 제6권1호
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    • pp.159-162
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    • 2006
  • This study generally compared and investigated cement type and quality of China and Korea. Cement in Korea is divided into five such as ordinary, high early strength, moderate heat, low heat and sulfate resistance portland cement. However cement in China is divided into portland cement($P{\cdot}I,\;P{\cdot}II$) and ordinary portland cement($P{\cdot}O$) with admixture displacement ratio and it is again divided into 6 level and 7 level with 28 days compressive strength. In addition China classified cement into several standards, such as Mgo, SO3,, igloss, blame, setting time, stability, strength, alkali and sampling test. Therefore it should be careful to conclude so quickly without right understanding whether quality of China cement is bad or good. The better way to evaluate China cement is synthetically understanding a value engineering and consumer awareness.

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저열 포틀랜드 시멘트를 사용한 고유동콘크리트의 사용재료 및 배합 변동에 따른 특성 평가 (The Effect on the Properties of High Flowing Concrete Using Low Heat Portland Cement by Material and Mixing Variations)

  • 하재담;김태홍;유재상;이종열;권영호
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 2001년도 가을 학술발표회 논문집
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    • pp.303-308
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    • 2001
  • Recently, concrete structures have become larger and higher and are demanding high performance concrete with lower heat to prevent thermal cracking, far greater workability, high strength and durability, Application of low heat portland(Type IV) cement for the high performance concrete is the best solution to satisfied those requirements. Here are explained the effect on the properties of high flowing concrete using low heat portland cement by material and mixing variations. Variables for sensitivity test were selected items like finess modulus of aggregates, particle size of limestone powder, unit water, superplasticizer, viscosity agent and concrete temperature. The results of this study were be applied to slurry wall of #215 and #216 of underground LNG tank in Inchon.

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