• 제목/요약/키워드: concrete separation

검색결과 218건 처리시간 0.027초

전기적 펄스를 이용한 폐콘크리트로부터의 재생골재 분리 연구 (Electrical pulse separation of construction materials)

  • 유광석;안지환;;한기천
    • 한국자원리싸이클링학회:학술대회논문집
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    • 한국자원리싸이클링학회 2005년도 춘계임시총회 및 제25회 학술발표대회
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    • pp.109-112
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    • 2005
  • The electrical pulse separation of concrete samples for the recycling purpose has been investigated by the electrical disintegration method using the discharged high voltageimpulse. First, when the consumed energy increased in electrical crushing, fracture section area increased clearly. This result suggests that crushing energy was consumed efficiently. Secondly, when conventional crushing after electrical disintegration is compared with only conventional crushing, gravels are more stable after electrical crushing. Thus, electrical crushing makes it easy to recover gravels from wasted concrete. In the next year, more efficient recovery of gravel for wasted concrete by electrical disintegration will be investigated. Thus, actual wasted concrete crushing by electrical separation and combination of conventional crushing will be carried out.

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시공성 향상을 위한 고강도 콘크리트 분리타설재 개발에 관한 연구 (Study on the horizontally perpendicular separation casting method of construction for execution improvement of the high strength concrete)

  • 최종문;김우재
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2011년도 춘계 학술논문 발표대회 2부
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    • pp.61-62
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    • 2011
  • In recent years, domestic construction companies have developed a 200MPa grade high-strength concrete and promoting the superiority of each technique. However, applying design and construction practices of developed high-strength concrete are weak. Most applications is limited to partial use and then the actual examples only used as a layer of high-rise building outrigger with casting some test on basement' vertical structures. In this study, developed materials for separation casting through joint research have been examined economy and others by field application and improving the workability.

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투명접합분리 시험체를 활용한 고강도 콘크리트의 강도관리에 관한연구 (Compressive Strength Control of High Strength Concrete Using Transparent Joint Separation Test Body)

  • 기전도;정광식;김학영;김광기;이영도;정상진
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2009년도 춘계 학술논문 발표대회 학계
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    • pp.49-52
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    • 2009
  • This paper aims to evaluate hydration and intensity property of different kind of members and intensity in order to evaluate compressive strength of structural concrete using Joint Separation Test Body(JSTB). In fact it is difficult to test and evaluate already have constructed member. In this case, common method used by construction engineer is that ; Schmidt rebound hammer test, Ultrasonic pulse test, Method of using test specimen previously cast. However, these method to control the structural intensity involve many problem and impossibility to adapt construction. 80, this paper proposes advance an opinion which have proper to examine intensity. has also aims to examine its validity and the plan to make similar environment with structural concrete and joint separation test body in order to verify efficiency assessment and on-site application.

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강-콘크리트 계면파괴에 관한 비선형 유한요소해석 (Nonlinear Finite Element Analysis of Considering Interface Behaviors between Steel and Concrete)

  • 주영태;이용학
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 2004년도 추계 학술발표회 제16권2호
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    • pp.105-108
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    • 2004
  • In general, the nonlinear behavior of composite structures composing of steel and concrete is analyzed on the basis of the assumption of the perfect bond actions in steel-concrete interface in which the interface slip or separation is not allowed. The assumption is based on the fact that the full interface bond behavior is provided with the mechanical connectors of studs. However, since the number and spacing of the studs are determined by the stress resultants calculated in the interface area, the interface analysis is required to evaluate the stress resultants. This paper describes the nonlinear steel-concrete interface behavior considering the two interface failure mechanisms of slip and separation. Elastoplastic constitutive relation is developed. thru the formulation framework using the two energy dissipation mechanisms. As the result, the steel plate push-out tests sandwitched between concrete blocks are analyzed and compared with the test results with which the good agreements are observed.

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투명 접합분리 몰드를 사용한 구조체 콘크리트의 수화특성 및 강도특성 관한연구 (An Experimental Study on Hydration Property and Intensity Property of Structural Concrete Using Transparent Joint Separation Test Body)

  • 기전도;박흥이;정광식;김광기;이영도;정상진
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 2009년도 춘계 학술대회 제21권1호
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    • pp.405-406
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    • 2009
  • 본 연구는 구조체 콘크리트의 강도를 평가 관리 하기 위해 구조체 콘크리트와 접합분리 시험체의 수화특성 및 강도특성을 평가 분석하여 타당성을 검토하고 구조체 콘크리트와 유사한 환경을 만들기 위한 방안을 검토하는데 목적이 있다

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고층건물 콘크리트 슬래브에서 분리대의 효과 (Effect of Separation Strip on the Concrete Slabs in High Rise Building)

  • 김한수;조석희
    • 한국전산구조공학회:학술대회논문집
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    • 한국전산구조공학회 2000년도 봄 학술발표회논문집
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    • pp.238-245
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    • 2000
  • Separation strips are temporary joints to prevent crack due to stress induced by shrinkage. In this study, an analysis procedure considering separation strip is proposed to decide proper casting time of separation strip and cracking stresses of the example building slabs are calculated using this procedure. The result of the example high rise building shows that the percentage of cracking stress to the modulus of fracture is 43.4% when closing of separation strip are 30 days after placing the slab, so it is enough time for the separation strip in each floor to absorb the effects of shrinkage.

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투명 접합분리 몰드를 사용한 고강도 콘크리트의 강도특성에 관한연구 (An Experimental Study on Intensity property of High Strength Concrete Using Transparent Joint Separation Test Body)

  • 기전도;박현;김광기;백민수;이영도;정상진
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 2009년도 춘계 학술대회 제21권1호
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    • pp.411-412
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    • 2009
  • 본 연구는 구조체 콘크리트의 강도를 평가, 관리 하는 기법이 건설현장에서 많은 문제점과 어려움을 내포하고 있어 이에 본 연구는 접합분리 시험체를 이용 구조체 콘크리트를 강도평가 하여 구조성능평가 및 현장 적용성 검증에 목적이 있다.

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Effect of Surface Condition and Corrosion-Induced Defect on Guided Wave Propagation in Reinforced Concrete

  • 나원배
    • 한국해양공학회지
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    • 제20권6호
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    • pp.1-6
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    • 2006
  • Corrosion of reinforcing steel bars is a major concern for ocean engineers when reinforced concrete structures are exposed to marine environments. Evaluating the degree of corrosion and corrosion-induced defects is extremely necessary to pursue a proper retrofit or rehabilitation plan for reinforced concrete structures. A promising inspection should be carried out for the evaluation, otherwise the retrofit or rehabilitation process would be useless. Nowadays, ultrasonic guided wave-based inspection techniques become quite promising for the inspection, mainly because of their long-range propagation capability and their sensitivity to different types of defects or conditions. Evaluating haw the guided waves response to the different types of defects or conditions is quite challenging and important. This study shows how surface conditions of reinforcing bars and a corrosion-induced defect, separation, affect guided wave propagation in reinforced concrete. Experiments and associated signal analysis show the sensitivity of guided waves to the surface conditions, as well as the amounts of separation at the interface between. concrete and steel bar.