• 제목/요약/키워드: Freezing-thawing resistance

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Evaluation on Surface Scaling and Frost Resistance for concrete Deteriorated due to Cyclic Freezing and Thawing with Inherent Chloride

  • Kim, Gyu Yong;Cho, Bong Suk;Lee, Seung Hoon;Kim, Moo Han
    • Corrosion Science and Technology
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    • v.6 no.4
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    • pp.177-185
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    • 2007
  • The purpose of this study is to evaluate freezing-thawing and surface scaling resistance in order to examine the frost durability of concrete in a chloride-inherent environment. The mixing design for this study is as follows: 3 water binder ratios of 0.37, 0.42, and 0.47; 2-ingredient type concrete (50% OPC concrete and 50% ground granulated blast-furnace slag), and 3-ingredient type concrete (50% OPC concrete, 15% fly ash, and 35% ground granulated blast-furnace slag). As found in this study, the decrease of durability was much more noticeable in combined deterioration through both salt damage and frost damage than in a single deterioration through either ofthese; when using blast-furnace slag in freezing-thawing seawater, the frost durability and surface deterioration resistance was evaluated as higher than when using OPC concrete. BF 50% concrete, especially, rather than BFS35%+FA15%, had a notable effect on resistance to chloride penetration and freezing/expansion. It has been confirmed that surface deterioration can be evaluated through a quantitative analysis of scaling, calculated from concrete's underwater weight and surface-dry weight as affected by the freezing-thawing of seawater.

Study on the Frost Damage of Self-Compacting Concrete in Cold Weather Regions (한랭지에 있어서 고류동콘크리트의 동해에 관한 연구)

  • ;;;;Miura, Takashi
    • Proceedings of the Korea Concrete Institute Conference
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    • 1999.10a
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    • pp.763-766
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    • 1999
  • The objective of this study was to investigate the influence of low temperature curing on resistance of freezing and thawing of self-compacting concrete placed in cold weather regions. The experimental study results indicated that the self-compacting concrete incorporating ground granulated blast-furnace slag showed good resistance to freezing and thawing, and the self-compacting concrete cellulose viscous agent had relatively poor resistance to freezing and thawing.

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Characteristics of Pore Structure and Chloride Penetration Resistance of Concrete Exposed to Freezing-Thawing (동결융해 작용을 받은 콘크리트의 공극구조 및 염화물 침투저항 특성)

  • Choi, Yoon Suk;Won, Min Sik;Yi, Seong Tae;Yang, Eun Ik
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.16 no.6
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    • pp.73-81
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    • 2012
  • Concrete structures are commonly exposed to freezing-thawing condition. This freezing-thawing action changes the pore structure of concrete, and it can reduce the durability of concrete. In this study, the change of the internal pore structure and durability of concrete due to freezing-thawing action are investigated. According to results, the excellent durability records were reported by the existing evaluation methods for all mixes. However, the pores, 50~100nm size in diameter, are increased in concrete specimens exposed to freezing-thawing action, and the chloride penetration resistance was significantly reduced. The linear relationship between pore structure and chloride penetration resistance was shown in water cured concrete. Meanwhile, the linear relationship was decreased when concrete is exposed to freezing-thawing condition. It is desirable to review the criterion of durability evaluation for concrete specimens exposed to freezing-fthawing and chloride attack condition, simultaneously.

The Relationship between Microstructure and Freezing Thawing Resistance of Polymer-Cement Mortars (폴리머-시멘트 모르타르의 미세구조 동결융합 저항성의 관계)

  • ;;田英治(Eiji Kamada)
    • Journal of the Korean Ceramic Society
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    • v.31 no.9
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    • pp.949-956
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    • 1994
  • In order to investigate the relationship between pore size distribution and freezing-thawing resistance of mortars, polymer-cement mortars were prepared by using styrene-butadiene rubber latex, ethylene-vinyl acetate emulsion and polyacrylic ester emulsion with various polymer-cement ratios at constant flow. From the results of the test, polymer-cement mortars had a good pore size distribution for freezing-thawing resistance compared with unmodified mortars because of having a small pore volume in the pore radius range of 103~104 $\AA$ affecting on the frost damage. And the freezing-thawing resistance of polymer-cement mortars was improved with increasing polymer-cement ratio.

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An Experimental Study on the Freezing and Thawing Resistance of Mortar Influenced by Steam Curing Conditions (증기양생조건이 시멘트 모르타르의 동결융해저항성에 미치는 영향)

  • Jang, Moon-Ki;Park, Kwang-Su;Kim, Kwan-Ho;Yoon, Seong-Soo
    • Proceedings of the Korean Society of Agricultural Engineers Conference
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    • 2001.10a
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    • pp.185-188
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    • 2001
  • In this study, the characteristics of freezing and thawing resistance, the compressive strength, and the change in height of cement mortar according to a steam and taler curing conditions has been studied. To this end, the major test variables include the period of the early curing, curing temperature and the later curing. The strength test as well as volume variousness have been conducted to explore the characteristics of freezing and thawing resistance on the curing conditions. The experimental results can be efficiently used to improve the characteristics of freezing and thawing resistance for concrete products carrying steam curing.

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A Study on the Freezing and Thawing Resistance of Permeable Polymer Concrete (투수성 폴리머 콘크리트의 동결융해 저항성에 관한 연구)

  • 박응모;조영국;소양섭
    • Proceedings of the Korea Concrete Institute Conference
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    • 1999.04a
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    • pp.331-336
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    • 1999
  • Permeable polymer concrete in this study is one of the environment conscious concrete that can be applied at road, side walks and river embankment, etc. The purpose of this study is to evaluate the effects of mix proportions such as resing content, filler-binder ratio and aggregate ratio on the freezing and thawing resistance of permeable polymer concrete. The permeable polymer concrete are prepared with the resin ratio of 5%, 6% and 7%, filler-binder ratio of 0, 0.5 and 1.0, and 2.5~5mm sized aggregate ratio to standard sand of 10:10, 10:20, 20:10 and 20:20. It is tested for freezing and thawing test according to ASTM C 666092, and then, weight change, length change, relative dynamic modulus, durability factor, and compressive and flexural strengths after test are measured. From the test results, the resistance to freezing and thawing of permeable polymer concrete increased with increase the resing content, filler-binder ratio and fine aggregate ratio.

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Effects of Micropores on the Freezing-Thawing Resistance of High Volume Slag Concrete (슬래그를 다량 치환한 콘크리트의 동결융해 저항성능에 미치는 미세공극의 영향)

  • Kim, Rae-Hwan;Kim, Gyu-Yong;Lee, Bo-Kyeong;Shin, Kyoung-Su;Song, Gwon-Yong
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.19 no.4
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    • pp.67-74
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    • 2015
  • In this study, effects of micropores on the freezing-thawing resistance of high volume slag concrete are reviewed. Concrete was made with slag which contains the ground granulated blast furnace slag(GGBS) and the pig iron preliminary treatment slag(PS) by replacing 0, 40, 70 %, then compressive strength, freezing-thawing resistance, micropores were reviewed. Also, specified design strength, target air contents were set. Deterioration was induced by using 14-day-age specimen which has low compressive strength for evaluating deterioration by freeze-thawing action. As results of the experiment, despite of specified design strength which has been set similarly and ensured target air contents, the pore size distribution of the concrete showed different results. Micropores in GGBS70 specimen have small amount of water which is likely to freeze because there is small amount of pore volume of 10~100 nm size at 0 cycle which has not been influenced by freezing-thawing. For these reasons, it was confirmed that the freezing-thawing resistance performance of GGBS70 is significantly superior than other specimens because relatively small expansion pressure is generated compared to the other specimens.

An Evaluation on Freezing and Thawing Resistance of Mortars with Bacillus licheniformis (Bacillus licheniformis 균주를 혼입한 모르타르의 동결융해 저항성 평가)

  • Hwang, Ji-Won;Yoon, Hyun-Sub;Yang, Keun-Hyeok
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2022.11a
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    • pp.237-238
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    • 2022
  • This study used Bacillus licheniformis generating glycocalyx as a provective membrane to enhance the salt-damage resistance of cement mortars. The mortar specimens with Bacillus licheniformis exhibited a comparable compressive strength development and 1.1~1.3 times higher dynamic modulus of elasticity under 300 freezing and thawing cycyles when compared with the counterpart control mortar.

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Compressive Strength and Resistance to Freezing and Thawing of Recycled Aggregate Concrete Containing Ground Granulated Blast Furnace Slag (고로슬래그 미분말을 혼입한 순환골재 콘크리트의 압축강도 및 동결융해 저항성)

  • Bae, Suho;Jeon, Juntai
    • Journal of the Society of Disaster Information
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    • v.9 no.4
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    • pp.469-475
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    • 2013
  • The purpose of this experimental research is to estimate compressive strength and resistance to freezing and thawing of recycled aggregate concrete containing ground granulated blast furnace slag. For this purpose, concrete specimens according to substitution ratio of recycled aggregate were made for different replacement ratio of ground granulated blast furnace slag(GGBFS), and then compressive strength and resistance to freezing and thawing were evaluated for those. It was observed from the test results that compressive strength at 28 days of recycled aggregate concrete containing GGBFS of 20% was much more excellent than plain concrete and when air content of concrete was maintained 4 to 6%, influence of substitution ratio of recycled aggregate and replacement ratio of GGBFS on resistance to freezing and thawing was little up to 300 cycles of freezing and thawing.

Evaluation of Stripping and Rutting Properties of CRM Modified Asphalt Mixtures (CRM 개질아스팔트 혼합물의 소성변형 및 박리저항 특성)

  • Doh, Young-S.;Park, Tae-W.;Kim, Hyun-H.;Kim, Kwang-W.
    • International Journal of Highway Engineering
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    • v.9 no.4
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    • pp.149-158
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    • 2007
  • Evaluation of the asphalt mixture modified with crumb rubber modifier(CRM) was performed to estimate possibility of using it as a paying material. OACs(optimum asphalt content) of CRM modified asphalt mixtures by dry process and wet process were determined by Marshall mix design and Wheel tracking test and moisture susceptibility test by freezing and thawing were carried out with CRM modified asphalt mixtures at OACs. The results from these tests, resistance of permanent deformation of CRM modified asphalt mixtures were superior to one of AP-5 while showing very low resistance of moisture sensitivity by freezing and thawing. This means that CRM modified asphalt mixtures are very sensitive to freezing and thawing. However, CRM modified asphalt mixture with anti-stripping material showed high improvement to resistance of moisture susceptibility by freezing and thawing. Therefore, it is recommended that when CRM mixtures were used in domestic, CRM modified asphalt mixtures should be with prevention against freezing and thawing resistance by moisture susceptibility.

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