• 제목/요약/키워드: concrete deterioration

검색결과 945건 처리시간 0.028초

해수의 영향을 받은 콘크리트의 동결융해 특성 (Properties on the Freeze-Thaw of Concrete Subjected to Seawater Attack)

  • 박광필;김성수;이승태;김종필;정호섭
    • 콘크리트학회논문집
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    • 제23권1호
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    • pp.23-30
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    • 2011
  • 이 연구는 콘크리트의 내구성 저하요인인 해수침식 및 동결융해 반복작용을 받은 콘크리트의 성능저하 정도를 실험적으로 고찰하기 위하여 포틀랜드 및 혼합시멘트를 사용하여 콘크리트 공시체를 제조한 후 상대동탄성계수, 압축강도 변화 및 기기분석을 통하여 성능저하 원인을 구명하였다. 동결융해 520싸이클까지의 결과 보통포틀랜드 및 저열포틀랜드시멘트는 75% 이상의 상대동탄성계수와 압축강도가 내황산염포틀랜드시멘트 약 44%의 값을 나타내어 상대적으로 낮은 저항성을 나타내었으며, 고로슬래그미분말을 50% 대체하여 사용한 콘크리트가 혼합시멘트계 콘크리트 중 가장 우수한 동결융해 저항성을 나타내었다. 혼합시멘트계 콘크리트의 해수침식 유 무에 따라 비교한 결과, 고로슬래그미분말 콘크리트의 잠재수경성 촉진으로 동결융해 저항성이 우수하였으나, 실리카퓸을 혼합한 콘크리트는 해수침식에 의한 성능저하가 발생하여 동결융해 저항성이 낮아지는 경향을 나타내었고, 해수침식 및 동결융해 작용을 받은 보통포틀랜드 콘크리트는 동결융해 작용에 의한 쏘마싸이트 피크와 해수침식에 의한 석고 및 프리델 염분 피크가 주로 검출되고, 고로슬래그미분말을 혼합한 콘크리트는 해수침식의 유 무에 상관없이 좋은 결과를 나타내었다.

알칼리회복제의 현장 적용성에 관한 실험적 연구 (To Experimental Study of Alkalinity Recovery Agent application in field)

  • 김광기;박선길;김우재;이영도;송병창;정상진
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2002년도 학술.기술논문발표회
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    • pp.7-10
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    • 2002
  • Concrete used up to date semipermanent architecture material but now day concrete early deterioration emboss social issue because of construction structure and environmental factor. so, many study of deterioration concrete construction improve durability used impregnation alkalization agent. In These to Study of derelop reoairmeat material in reduce carbonation. xoncrete Building use Alkalinity Recovery Agent which is Realkalinity and strength surface. Alkalinity Recovery Agent undisposed application volume and cure the concrete period. To study Alkalinity Recovery Ahent spray and cure the concrete propriery in field.

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전기저항형 센서 및 전기화학적 방법을 이용한 철근콘크리트 구조물의 부식속도 측정 방법에 관한 연구 (Study on The Corrosion Rate Monitoring of Steel in Concrete Using Electric resistance Sensor and Electrochemical Methods.)

  • 조용범;김용철;장상엽;고영태
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 2001년도 가을 학술발표회 논문집
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    • pp.1185-1192
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    • 2001
  • This paper reviews available techniques for monitoring corrosion of steel in concrete. The need for early detection and diagnosis of corrosion related deterioration in reinforced structures is widely acknowledged. This is particularly important in reinforced concrete structures on account of the economic and social significance of the problem. The current generally used on-site procedure for corrosion monitoring of reinforced structures employs a method of half-cell surface potential measurements. While the technique has provided a useful means of delineating areas of high or low corrosion risk, there are difficulties in its use and interpretation when assessing rates of deterioration. Electrochemical techniques are by far the most suitable for corrosion monitoring purpose and meet most of the requirements. The aim of this paper is to describe the electric resistance sensor(ER sensor) and electrochemical techniques employed to monitor and estimate corrosion rates of reinforcement. Early detection and diagnosis of corrosion hazards allows preventive measures to be taken, hence the typically expensive repair of severely deteriorated structures can be avoided.

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첨가 이온종류에 따른 외국 골재의 알카리.골재 반응성 조사연구 (한국 시멘트 사용 지역 중심) (Investigation of Alkali-Aggregate Reaction of Abroad Aggregates (Using Area of KOREA Cement))

  • 현석훈;엄태형
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 1995년도 봄 학술발표회 논문집
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    • pp.111-117
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    • 1995
  • The alkali-aggregate reaction is a reaction between the alkali metals in the pore water of a concrete and an unstable mineral of the aggregate. There are three types of alkali-aggregate reation which causes deterioration of concrete, such as alkali-silicate reation, alkali-carbonate reaction and alkali-silica reation. Deterioration due to alkali-silica reation is more comon than that due to either the alkali-silicate or alkali-carbonate reaction. The alkali-silica reation is a reaction between the hydroxyl ions in the pore water of a concrete and silica which exists in signigicant quantities in the aggregate. In this PAPER, Alkali-aggregate reactions of mortar made with various abroad aggregate were investigated using XRD, microscope, chemical and physical tests. In additions, the effects of the texture of aggregate, Na, K, CI ion concentrations added to the mortar, on these reactions were studied.

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세라믹계 나노물질을 이용한 침투성 방수제의 내구성능 개선효과 연구 (A Study on improving Effect of Durability Performance Using Penetration waterproofing Agent of Ceramic nano materials)

  • 류금성;박정준;고경택;김도겸;이장화
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 2004년도 춘계 학술발표회 제16권1호
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    • pp.176-179
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    • 2004
  • The latest concrete structure has showed that the deterioration of durability has been increased by the damage from salt, carbonization, freezing & thawing and the others. Therefore, the measures for the concrete which has deteriorated durability have been taken. Among them, it has been often used that surface treatment which cuts off the deterioration factors of durability by protecting the surface of concrete. This study was evaluated the surface improving agent for permeability, watertightness, air-permeability, chemical resistance and elution resistance.

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Strength and durability studies on high strength concrete using ceramic waste powder

  • Karthikeyan, B.;Dhinakaran, G.
    • Structural Engineering and Mechanics
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    • 제61권2호
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    • pp.171-181
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    • 2017
  • This paper summarizes the study on effect of ceramic waste powder as partial substitute to cement in binary blend and along with silica fume in ternary blend high strength concrete in normal and aggressive environments. Strength parameters such as compression & tension and durability indices such as corrosion measurement, deterioration, water absorption and porosity were studied. Ceramic waste powder was used in three different percentages namely 5, 10 and 15 with constant percentage of silica fume (1%) as substitutes to cement in ternary blend high strength concrete was investigated. After a detailed investigation, it was understood that concrete with 15% ceramic waste powder registered maximum performance. Increase of ceramic waste powder offered better resistance to deterioration of concrete.

강릉시 콘크리트 하수관거의 내구성 평가 (Estimation on Durability of Concrete Sewage in Kangnung City)

  • 최성하;최윤석;김강래;김명유;양은익
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 2006년도 춘계 학술발표회 논문집(II)
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    • pp.229-232
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    • 2006
  • Most of sewage in our country has been made by concrete, and currently they shows gradual deterioration. One of serious problems happened in the sewage is a corrosion of sewage itself. Namely, biochemical corrosion is the most important one. Deterioration phenomenon in concrete used in sewage is occurred by environment condition of sewage, such as erosion by the acid, erosion by sulfate, corrosion by carbonation and so on several factors. However, at present, investigation data on durability of Kangnung city sewage is not sufficient. In addition, the prediction of repair time and selection of rehabilitation method is also not easy. Accordingly, in this research, investigation on durability of sewages located in Kangnung city was carried out. It will also supply the basic data for repair and rehabilitation.

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실리케이트계열의 표면침투보강재를 이용한 열화방지기술개발 (Development of the Preventing Aging Technology Using Silicate Type Penetration Reinforcing Agent)

  • 김도겸;조명석;송영철;류금성
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 2006년도 춘계 학술발표회 논문집(II)
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    • pp.313-316
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    • 2006
  • The most serious cause of deterioration in the concrete structures is reinforcing corrosion due to the chloride attack and carbonation. Therefore, it is needed to protect durability and performance according to the appropriate materials and methods in the concrete structures. In general, several types of polymer and silicate are used as protecting deterioration agents of concrete structures, but these agents have many problems because of low durability and properties. The object of this study is to develop a preventing aging technology. The work involves the development of silicate type penetration reinforcing agent.

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콘크리트 라이닝 구조물의 누수에 의한 열화특성 (Effect of Leakage on Deterioration of Concrete Lining Structure)

  • 정호섭;김동규;김성수;박광필
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 2009년도 춘계 학술대회 제21권1호
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    • pp.287-288
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    • 2009
  • 본 연구에서는 과거에 축조되었던 노후터널에 대하여 현장조사를 통하여 터널 라이닝 콘크리트에 발생한 균열과 누수에 대하여 열화정도를 평가하였다. 터널 콘크리트 라이닝에 대하여 외관조사, 비파괴시험, 코어를 채취하여 압축강도 및 투수성 평가와 시편에 대한 기기분석을 실시하였다.

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화해를 입은 철근콘크리트 기둥의 구조성능 저하 (Deterioration of Structural Capacity of Fire-Damaged Reinforced Concrete Column)

  • 이차돈;신영수;홍성걸;이승환
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 2003년도 가을 학술발표회 논문집
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    • pp.371-374
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    • 2003
  • The degree of changes in mechanical properties of fire-damaged reinforced concrete column depends mostly on sectional geometry, duration exposed to fire, and moisture containment. In order to reasonably assess the deterioration of structural capacity of fire-damaged reinforced concrete column, it is necessary to develop a theoretical model predicting column behavior based on nonlinear heat transfer equation in addition to the traditional mechanics. This research focuses on the development of theoretical model to predict moment-curvature relations of fire-damaged reinforced column. The model is used for the assessment of structural capacity of fire-damaged column in terms of moment-curvature relations and PM interaction curves.

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