• 제목/요약/키워드: Fume

검색결과 793건 처리시간 0.026초

혼합재 및 입도에 따른 경량기포콘크리트의 강도특성 개선 (Improvement of Strength in ALC using Admixtures and Grain Size)

  • 김영엽;송훈;이종규;추용식
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2007년도 추계 학술논문 발표대회
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    • pp.79-82
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    • 2007
  • Recently, the use of ALC has became increasingly popular. ALC is a unique building material. Because of its cellular nature, it is lightweight, self-insulating, sound and fireproof, as well as insect and mold resistant. Furthermore, ALC is free of VOCs and various fibers associated with wood and glass wool construction. However, ALC have high water absorption, low compressive strength and popout the origin of the low surface strength in its properties. These properties make troubles under construction such as cracking and popout. Thus, this study is to improve the fundamental strength by controls of increasing of admixtures, and grain size. Admixtures make use of metakaolin, silica fume, sodium silicate and sodium hydroxide. From the test result, the ALC using admixture have a good fundamental properties compared with plain specimen. Compressive strength, specific strength and abrasion's ratio were improved depending on increasing admixtures ratio's, and grain size.

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원자짝 분포 함수를 이용한 플라이애시를 대량 치환한 시멘트 클링커의 나노 구조 변형 거동 해석 (Analysis of Nanostructural Deformation Behavior of Cement Clinker Substituting High-volume Fly ash by Pair Distribution Function)

  • 지현석;박재연;배성철
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2019년도 춘계 학술논문 발표대회
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    • pp.112-113
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    • 2019
  • Recently, supplementary cementitious materials such as blast-furnace slag, fly ash and silica fume have been widely used as substitutes for cementitious materials. In this study, the deformation behavior of compressive loading of C3S paste with 50% fly ash was analyzed by X-ray scattering data and pair distribution function analysis. The obtained results were compared with 131-day-old pure C3S paste. The Ca(OH)2 of the C3S-FA paste showed almost complete elastic behavior, consistent with the deformation behavior of the r-range of 20 to 40, and the C-S-H phase contributed to the range of PDF r-range of less than 20. In addition, C-S-H of C3S-FA showed greater deformation resistance than C3S paste.

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Micro FEM 해석에 의한 기포제 혼입 시멘트 페이스트의 역학적 성능 평가에 관한 연구 (A study on Mechanical Performance Evaluation of Cement Paste Using Foaming Agent by Micro FEM Analysis)

  • 김보석;우영제;이한승
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2015년도 춘계 학술논문 발표대회
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    • pp.55-56
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    • 2015
  • This study is corroborated as a fundamental resource to develop structural lightweight paste containing silica fume as a part of cement. Paste using foaming agent is generated much foam and decreased density of paste. This study is measured at 0.8% of foaming agent dosage but over 0.8% of foaming agent dosage raise density of paste because of interconnection with foam. Also, FEM analysis using SEM image is confirmed correspondence of between Elastic modulus of experiment and FEM analysis.

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3성분계 무시멘트 모르타르의 강도발현 특성 (Strength Development of No Cement Ternary Mortar)

  • 정유진;김영수
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2018년도 추계 학술논문 발표대회
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    • pp.108-109
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    • 2018
  • Cement is the most widely used but generates a lot of CO2, so we need a material to replace it. Using industrial by-products such as Silica Fume(SF), Blast furnace Slag(BS) and Fly Ash(FA) bring some advantages including CO2 reduction and resource recycling. However, there is a limit to improve performance when using only one material. Therefore, the synergy effects of No cement binary mortar and ternary mortar were analyzed and compared. As a result, No cement ternary mortar had the strength higher than binary mortar. among ternary mortars, the specimen mixed 50% of BS had the highest strength. However, when SF was mixed by 20%, the flowability reduces. so 10% of SF, 40% of FA and 50% of BS is considered as the optimal mixing ratio.

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3성분계 무기결합재 패널크기에 따른 건조수축 특성 (Dry Shrinkage Characteristic according to the Ternary System Inorganic Binder Panel Size)

  • 이진우;이상수
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2014년도 추계 학술논문 발표대회
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    • pp.144-145
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    • 2014
  • In the cement,that is the main materials of the panel, as to the cofired process, more than 1,300 enormous energies is consumed, in addition the greenhouse gas generated in the process of producing the cement occupies 6.3% of the country whole emission quantity. And the carbon dioxide of about 0.8 ton is the cement ejected in 1 production. Accordingly, the panel utilizing the industrial byproduct is developed. Accordingly, this research is the experiment which makes the individual size into the environment-friendly inorganic binder panel and by using the blast furnace slag, which is the industrial byproduct with the cement substitute material red mud, silica fume, and etc. looks at the dry shrinkage. The length variation in which the panel which is 450 with the dry shrinkage result of measurement, thickness 12mm, and size 450mm is the smallest was shown.

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Push-Pull 국소환기시스템 개선에 관한 수치해석 (A Numerical Analysis on Improvement of Push-Pull Local Ventilation System)

  • 이중섭;장성철;윤강로
    • 대한설비공학회:학술대회논문집
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    • 대한설비공학회 2007년도 동계학술발표대회 논문집
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    • pp.594-599
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    • 2007
  • This study represents numerical analysis on the fluid flow and concentration characteristics by scattering fume at push-pull ventilation system. And the principal point is making optimum on improve an existing ventilation system. This phenomenon simulated about local ventilation system by using commercial CFD tool and base on these fact has find improvements. Advanced model shows most low different pressure and velocity which are suction capability at inlet surface of pull hood has most uniformity. When compared with existing model, Improved model has more good ventilation performance.

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Ergonomic Evaluation of Some University Laboratories

  • Lee, Yun Keun;Lee, Ik Mo;Park, Jeongim;Yoon, Chung Sik;Rhie, Kwang Won;Park, Hee Sok
    • 대한인간공학회지
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    • 제32권4호
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    • pp.397-403
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    • 2013
  • Objective: This article aims to report the results of ergonomic evaluation of some university laboratories. Background: Laboratory researchers are at risk for musculoskeletal injuries during routine laboratory procedures. However, little attention has paid to the working conditions of laboratory researchers, especially in Korea. Method: A checklist and questionnaire was developed and used to analyze the work conditions of 27 laboratories of chemistry, biology and pharmacy. Results: It was found that glove box, clean bench, and computer workstation are better than microscopy, and fume hood tasks, from ergonomic point of view. Conclusion: No domestic guideline is available for ergonomic intervention of laboratories. Further attention and studies are anticipated to improve the working conditions of laboratories.

Development of Metallic Bipolar Plate Material with W-addition in Austenitic Stainless Steel for PEMFC Environment

  • Kim, Kwang Min;Koh, Sung Ung;Kim, Kyoo Young
    • Corrosion Science and Technology
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    • 제5권5호
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    • pp.153-159
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    • 2006
  • Austenitic stainless steels with addition of various amounts of Mo and W were evaluated in terms of corrosion and contact resistance to determine optimum alloy composition of metallic bipolar plate for PEMFC. The corrosion property was evaluated by both acid fume exposure test at $130^{\circ}C$ and by electrochemical polarization tests in $H_3PO_4$ solution at $80^{\circ}C$. Austenitic stainless steel with proper amount of Mo and W demonstrated not only good corrosion resistance but also low contact resistance. Analyses on the passive film show that partial substitution of Mo by W enhances passive film stability and repassivation property. Test results suggest that austenitic stainless steel with 2 wt%Mo and 4 wt%W has optimum composition for metallic bipolar plate used in PEMFC.

염분환경하 콘크리트 경화체의 내구성에 미치는 혼합재의 영향 II. 콘크리트의 동결융해저항성 (Effect of Blending Materials on the Durability of Concrete II. Freezing and Thawing Resistance of Concrete)

  • 정재동;김원기;정용;한기성;최상흘
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 1991년도 가을 학술발표회 논문집
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    • pp.34-39
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    • 1991
  • It is well-known that concretes under sea water environment show remarkably degrading phenomena physically by repeatable freeze-thawing action and chemically by penetration of soluted ions in sea water. In this study the influences of type of blending materials, their dosage and W/C ratio on freeze-thawing resistances of hardened cement concrete using foy ash, ground blast furnace slag, silica fume, EVA and SBR under sea-water environment were investigated.

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섬유보강 시멘트 복합체의 동결융해 저항성 및 섬유형태별 역학적 특성에 관한 연구 (An Experimental Study on the Freeze-Thaw Durability and Mechanical Properties by the fiber types of Fiber Reinforced Cement Composites)

  • 박승범;윤의식;송용순
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 1990년도 가을 학술발표회 논문집
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    • pp.145-150
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    • 1990
  • In order to discuss the freeze-thaw durability of FRC and mechanical properties by the fiber types of FRC, experimental studies of FRC were carried out. The kinds of fiber used which are in CFRC are PAN-based and Pitch-based carbon fiber and in GFRC are alkali-resistance glass fiber. To examine the effects of the kinds, types (continuous fiber and Tow, Belt, Cloth) and contents of fiber and matrices, the following three methods CFRC and GFRC, Air cured, Water cured and Autoclaved CFRC and GFRC were tested. According to the test results, the flexural, tensile strength and toughness of FRC were remarkably influenced by types of fiber and addition of condensed silica fume. Also, freeze-thaw resistance of FRC was considerably improved in comparision to conventional mortar.

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