• Title/Summary/Keyword: Resistance to Freeze-Thaw

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Near surface characteristics of concrete: prediction of freeze/thaw resistance

  • Chan, Sammy Yin Nin;Dhir, Ravindra K.;Hewlett, Peter C.;Chang, Da Yong
    • Structural Engineering and Mechanics
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    • v.2 no.4
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    • pp.403-412
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    • 1994
  • The durability of concrete is related to the permeation characteristics of its near surface. An attempt was made to use the permeation characteristics namely, absorptivity, permeability and diffusivity, to predict the freeze/thaw resistance of concrete. Test results indicate that in general, there was a trend that freeze/thaw resistance of concrete was enhanced with improved absorptivity and diffusivity whilst the freeze/thaw resistance of normal concrete was found to have the best relationship with its intrinsic permeability. The latter method is therefore proposed to be adopted to predict freeze/thaw resistance of normal concrete. Since Figg air test is an inexpensive and simple test method that measures indirectly the intrinsic permeability of concrete, it is further proposed that it could be used as a quality control tool to assess, non-destructively, the freeze/thaw durability potential of in-situ concrete.

Effect of Polymers on the Freezing and Thawing Resistance of Hardened Cement Mortar (시멘트 경화체의 동결융저항성에 미치는 Polymer의 영향)

  • 이선우;김정환;최상흘;한기성
    • Journal of the Korean Ceramic Society
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    • v.28 no.7
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    • pp.509-516
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    • 1991
  • The effect of various polymers on the freeze-thaw resistance of hardened cement mortar was investigated. For this study, styrene butadiene rubber (SBR), ethylene vinyl acetate (EVA), polyvinyl alcohol (PVA) were used to prepare cement mortar specimen, and then freeze-thaw experiment was carried out. By adding SBR adn EVA to the specimen, the freeze-thaw resistance of specimens was improved, but when PVA was added to the specimen, its freeze-thaw resistance was lowered. Particularly, the specimens which were added 5, 10% of SBR and 5% of EVA showed excellent freeze-thaw resistance in the salt environment.

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An Experimental Study on the Freeze-Thaw Resistance of Concrete Containing Waste Glass (폐유리를 혼입한 콘크리트의 동결융해 저항성에 관한 실험적 연구)

  • Park, Seung-Bum;Cheong, Myeong-Il;Lee, Bong-Chun;Lee, Jun
    • Proceedings of the Korea Concrete Institute Conference
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    • 2002.05a
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    • pp.593-598
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    • 2002
  • Recently, as industrialization is rapidly growing and the standard of life is rising, the quantities of waste glasses have been hastily increased and most of them are not recycled but abandoned. It causes some problems such as the waste of natural resources and environmental pollution. Therefore, in this study freeze-thaw resistance test was conducted to analyze the properties of concrete containing waste glasses as fine aggregates and containing industrial by-products (fly ashes, silica fumes). As a results, it was found that freeze-thaw resistance decreases as the content of waste glasses increases. Also, the content of fly ash doesn't affect to the freeze-thaw resistance, and freeze-thaw resistance decreases with tile increase of silica fume contents.

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Performance of paraffin mixed concrete subjected to combined freeze-thaw and chloride environment

  • Hiroshi Maruta;Dhruva Narayana Katpady;Hirotaka Hazehara;Masashi Soeda
    • Advances in concrete construction
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    • v.17 no.1
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    • pp.45-52
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    • 2024
  • In this study, the fresh properties of paraffin-mixed concrete, compressive strength, resistance to frost damage, and resistance to composite deterioration under freeze-thaw and salt environment were investigated. The compressive strength of paraffin-mixed concrete was almost the same as that of unmixed concrete, and no decrease in strength was observed, unlike the concrete with entrained air in consideration of freeze-thaw resistance. Concerning the freeze-thaw resistance of paraffin-mixed concrete, the relative dynamic modulus of elasticity (RDME) did not decrease even without entrained air. In addition, no decrease in the RDME was observed in the combined deterioration with salt damage, and it was confirmed that the mass reduction was suppressed compared to the concrete without paraffin. The freeze-thaw resistance of concrete when paraffin is mixed may be improved due to the reduction in the amount of frozen water and the mixed paraffin particles exist in the concrete as pore fillers with a size of 200 ㎛ or less, which act as substitutes for air voids. This resulted in reduction of the apparent air void spacing and thereby relieving the pore pressure.

A Study on the Freeze-Thaw Resistance of Porous Concrete Using Polymer (폴리머를 이용한 포러스 콘크리트의 동결융해저항성에 관한 연구)

  • Lee, Sang Tae
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.9 no.3
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    • pp.17-25
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    • 2006
  • To increase freeze-thaw resistance of porous concrete, this study examined physical properties of polymer by replacing paste used as a binding material with polymer, using unsaturated polyester and epoxy resin, and changing the mixing ratio of polymer. According to the result of this study, when the mixing ratio of resin paste to aggregates was 11 to 16%, voids volume was 33 to 37% and unit weight was about 1620 to 1720kg/$m^3$. In comparison with previous studies using cement paste, voids volume increased by about 7 to 16%, while unit weight decreased by about 100 to 300kg/$m^3$. Compressive strength was 90 to 155kg/$cm^2$ at the age of 7 days, which was 5-40kg/$cm^2$ bigger than porous concrete using cement paste. From a viewpoint of freeze-thaw resistance, it was identified that pluse velocity fell by 0.23km/sec, about 7% of the original velocity, when the cycle of freeze-thaw was repeated 300 times. In spite of 300 repetitions of the cycle, relative dynamic modulus of elasticity was more than 60%, which suggested that its freeze-thaw resistance was more excellent compared with the result that relative dynamic modulus of elasticity of porous concrete using cement paste was 60 % or less under the condition of 80 repetitions of freeze-thaw cycle.

Freeze-Thaw Resistance of Blended Cement Concrete using Seawater (해수를 사용한 혼합시멘트계 콘크리트의 동결융해 저항성)

  • 문한영;김성수;이승태;김종필;박광필
    • Proceedings of the Korea Concrete Institute Conference
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    • 2002.05a
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    • pp.725-730
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    • 2002
  • The durability of concrete involves resistance to freeze-thaw action, corrosion, permeation, carbonation, chemical attack and so on. Generally, properties of concrete have been well understood under the separate action of these deterioration mechanisms. However, in practice, the degradation of concrete usually is the result of combined action of physical and chemical attack and can be accelerated by the combined action of several deterioration mechanisms. In the present study, to evaluate the combined deterioration by freeze-thaw action and seawater attack, ground granulated blast-furnace slag or silica fume concrete with water or seawater as mixing water was exposed to 210 cycles of freeze-thaw action. Tests were conducted to determined the relative dynamic modulus of elasticity and compressive strength. Furthermore, The XRD, SEM and EDS analysis were performed on the deteriorated part of concrete due to freeze-thaw action and seawater attack.

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Microstructure and Freeze-Thaw Resistance of Portland Cement Mortars (포틀랜드 시멘트 모르타르의 미세구조와 동결융해저항성에 대하여)

  • 이종호;장복기
    • Journal of the Korean Ceramic Society
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    • v.28 no.11
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    • pp.917-925
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    • 1991
  • For the present experiment five Portland cement mortars are in order: mortars with two different water/ cement ratios (W/C=0.45 and 0.50, each having no chemical additive), and those with an additive such as superplasticizer, air-entraining agent or water-repelling agent. We fix the W/C ratio of mortars having additive so that their pastes can yield the same workability as that of the cement mortar of W/C=0.50 with no additive. It is shown that the freeze-thaw resistivity depends heavily on the characteristic of wide pores. Despite a good deal of wide pores, the air-entrained specimen shows a good freeze-thaw resistivity due to appropriate air-pores. And also the specimen with water-repelling agent, which proves to cause the microstructure to become hydrophobic, make good resistance to freeze-thaw cycles in spite of its high wide-porosity. Our suggestion is that the freeze-thaw durability of Portland cement mortar/concrete can be more effectively enhanced by using air-entraining agent or water-repelling agent, and simutaneously by taking proper measures against foaming and/or the increased tendency of wide-pore building due to additive.

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Freeze-Thaw Resistance and Void Characteristic of Blended Cement Concrete using Seawater (해수를 사용한 혼합시멘트계 콘크리트의 동결융해 저항성 및 공극특성)

  • Kim, Seong-Soo;Lee, Seung-Tae;Jung, Ho-Seop;Park, Kwang-Pil
    • Proceedings of the Korea Concrete Institute Conference
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    • 2006.11a
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    • pp.589-592
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    • 2006
  • The durability of concrete involves resistance to freeze-thaw action, corrosion, permeation, carbonation, chemical attack and so on. Generally, properties of concrete have been well understood under the separate action of these deterioration mechanisms. However, in practice, the degradation of concrete usually is the result of combined action of physical and chemical attack and can be accelerated by the combined action of several deterioration mechanisms. In the present study, to evaluate the combined deterioration by freeze-thaw action and seawater attack, ground granulated blast-furnace slag or silica fume concrete with water or seawater as mixing water was exposed to 300 cycles of freeze-thaw action. Tests were conducted to determined the relative dynamic modulus of elasticity and compressive strength. Furthermore, The MIP analysis were performed on the deteriorated part of concrete due to freeze-thaw action and seawater attack.

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The effects of different cement dosages, slumps and pumice aggregate ratios on the freezing and thawing of concrete

  • Turkmen, Ibrahim;Demirboga, Ramazan;Gul, Rustem
    • Computers and Concrete
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    • v.3 no.2_3
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    • pp.163-175
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    • 2006
  • This research was conducted to determine effect of pumice aggregate ratio, cement dosage and slumps on freeze-thaw resistance, density, water absorption and elasticity of concrete. In the first batch, $300kg/m^3$ cement dosage were kept constant and pumice ratios were changed as 25%, 50%, 75% and 100% of replacement for normal aggregate by volume for $3{\pm}1cm$, $5{\pm}1cm$ and $7{\pm}1cm$ slumps. Other batches were prepared with $200kg/m^3$, $250kg/m^3$, $350kg/m^3$, $400kg/m^3$ and $500kg/m^3$ cement dosages and 25% pumice aggregate +75% normal aggregate at a constant slump. Test results showed that when pumice-aggregate ratio decreased the density and freeze-thaw resistance of concretes increased. With increasing of cement dosage in the mixtures, density of the concretes increased, however, freeze-thaw resistance of concretes decreased. Water absorption of the concrete decreased with increasing cement dosage but increased with the pumice ratio. Water absorption of the concrete also decreased after freeze-thaw cycles. Freeze-thaw resistance of concretes was decreased with increasing the slumps.

Evaluation of Crack Resistance of Cold Joint as Usage of Sealing Tape (실링 테이프 적용에 따른 시공조인트 균열 저항성 평가)

  • Lee, JaeJun;Lee, Seonhaeng;Kim, Du-Byung;Lee, Jinwook
    • International Journal of Highway Engineering
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    • v.20 no.3
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    • pp.1-9
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    • 2018
  • PURPOSES : In order to evaluate a crack resistance at cold joint, sealing tape was adopted to apply at cold joint instead of typical tack coat material(RSC-4). The sealing tape was made by hot sealing material. The crack resistance as function of environmental and traffic loading was measured with visual observation. METHODS : In this study, the crack resistance was evaluated as function of environmental and traffic loading. The freeze-thaw method was adopted for environmental loading of asphalt pavement. condition. The damage of cold joint under freeze-thaw action is initiated by ice expansion load and accelerated by the interfacial damage between new and old asphalt pavement. The traffic loading was applied with wheel tracking machine on the cold joint area of the asphalt pavement for 3 hours at $25^{\circ}C$. The evaluation of crack resistance was measured with visual observation. The freeze-thaw results shows that the sealing tape was significantly increased the crack resistance based on. RESULTS : To estimate the crack resistance at cold joint area due to the environmental loading, the Freeze-thaw test was conducted by exposing the product to freezing temperature(approximately $-18^{\circ}C$) for 24 hours, and then allowing it to thaw at $60^{\circ}C$ for 24 hours. The tack coat material(RSC-4) was debonded after 21 cycles of the Freeze-thaw test. The first crack was observed after 14 freeze-thaw cycle with RSC-4 material. But, the sealing tape was not debonded after 24 cycle test. Also, the sealing tape shows the better performance of the crack resistance under the traffic loading with wheel track test. The crack was generated the under traffic loading with RSC-4(tack coating), however, the crack was not shown with sealing tape. It indicates that the sealing tape has a strong resistance of tensile stress due to traffic loading. CONCLUSIONS :Based on limited laboratory test result, a performance of crack resistance using the sealing tape is better than that of general tack coat material(RSC-4). It means that the sealing tape is possible to extend a pavement service life because the crack, one of the main pavement distresses, will be delayed.