• Title/Summary/Keyword: freezing and thawing resistance test

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Investigation on the Method of Evaluating the Resistance to Freezing and Thawing of Concrete Subjected Initial Frost Damage (초기동해를 받은 콘크리트의 내동해성 평가법에 대한 검토)

  • 고경택;장일영
    • Journal of the Korea Concrete Institute
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    • v.11 no.4
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    • pp.117-127
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    • 1999
  • In concrete incorporating high volume ground granulated blast-furnace slag that has frozen at early age, to evaluated the results of resistance to freezing and thawing is very difficult because the hydration of the concrete increases over the duration of rapid freezing and thawing test. Hence, the dynamic modulus of elasticity of specimens after freezing and thawing will be favorable results unless the hydration effect is taken into consideration. In this study, a method of evaluating to the resistance to freezing and thawing of concrete subjected freezing at early age, in which the effect of hydration is modified for its increase during rapid freezing and thawing test, is investigated.

An Experimental Study on Freezing-Thawing Resistance of Concrete Using Ground Granulated Blast-Furnace Slag (고로슬래그 미분말을 사용한 콘크리트의 동결융해 저항성에 대한 실험적 연구)

  • 남용혁;최세규;김동신;김생빈
    • Proceedings of the Korea Concrete Institute Conference
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    • 1996.10a
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    • pp.148-153
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    • 1996
  • Concrete with ground granulated blast-furnace slag can be affected by frost attack because the reaction of hydration is slow at the early age. In this study, therefore, the freezing and thawing test has been carried out to investigate the freezing and thawing resistance on concrete with ground granulated blast-furnace slag. The freezing and thawing test has been performed on concrete a blended cement, which was substituted by ground granulated blast-furnace slag with 4 kinds of ratio (non-admixture, 20%, 40% and 60%). And also tested on concrete added the AE agents to the concrete of same mix proportion to search the improvement effects about the resistance. As a result, the freezing and thawing resistance showed a tendency of reduction in proportion to the increase of the substitution ratio. For non-AE concrete, resistances of the freezing and thawing were very poor as the durability index indicated less than 5.8%. For AE concrte, resistance of the freezing and thawing were excellent as the durability index indicated more than 80.9%.

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An Experimental Study on Freezing and Thawing Resistance of Fly Ash Concrete (플라이애쉬 콘크리트의 동경융해저항성에 관한 연구)

  • 배성용
    • Journal of Ocean Engineering and Technology
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    • v.15 no.3
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    • pp.128-133
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    • 2001
  • It is generally known that the concrete structure subjected to severe environment is much affected by the corrosion of reinforcement, the freezing and thawing action of concrete structure. The main objective of this study is to investigate the freezing and thawing resistance of concrete including fly ash. The effect of the air content in concrete using fly ash is investigated. The experimental study is conducted for 10 mix-ratio cases of concrete of which variables are content of fly ash, concrete compressive strength and containment of air-entrained admixtures. Test results show that the freezing and thawing resistance improves as the amounts of fly ash increase, and concrete with air-entrained admixtures has good freezing and thawing resistance. The concrete with fly ash is to be included air-entrained admixture according to content of fly ash in order to increase the freezing and thawing resistance.

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Characteristics of Lightweight Aggregate Concrete according to Freezing and Thawing Resistance Test Methods (동결융해 저항성 시험방법에 따른 경량골재 콘크리트의 특성)

  • Kim, Se-Hwan;Kim, Sang-Heon;Lee, Soo-Hyung;Jeon, Hyun-Kyu;Seo, Chee-Ho
    • Journal of the Korea Institute of Building Construction
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    • v.13 no.3
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    • pp.202-208
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    • 2013
  • The method used to test lightweight aggregate concrete for its resistance to freezing and thawing is different in each country. In Korea, the method of KS F 2456 on normal concrete is adopted for lightweight aggregate concrete, while the testing method of ASTM C 330 lightweight aggregates for structural concrete is used in the majority of overseas countries. In this study, we identified differences between KS F 2456 and ASTM C 330 in terms of the testing method for freezing and thawing resistance, and we studied the influence of this on the freezing and thawing resistance of lightweight aggregate concrete. The results of this study were as follows: Blocked lightweight aggregates had a slight collapse of shape and lost weight by repeated freezing and thawing, but unblocked lightweight aggregates were badly collapsed. And while the freezing and thawing resistance tests of normal concrete showed similar results despite the difference in the KS and ASTM testing method, the results for lightweight aggregate concrete were very different. So the KS test method shows evaluation results that are much lower than the ASTM test method.

Freezing-Thawing Resistance of Concrete Using Steel Slag as Coarse Aggregate (제강슬래그를 굵은 골재로 이용한 콘크리트의 동결융해 저항성)

  • Lee, Hyo-Seong;Han, Sang-Ho
    • Journal of Advanced Engineering and Technology
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    • v.11 no.4
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    • pp.295-301
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    • 2018
  • In this study, freezing-thawing resistance of concrete using steel slag as coarse aggregate(steel slag concrete) from Gwangyang Iron Co. was estimated to offer basic data for utilization of much more steel slag. Freezing-thawing test of concrete using crushed stone as coarse aggregate(crushed stone concrete) whose compressive strength and air contents are as close as possible to those of the steel slag concrete was performed. Because they are main two factors that affect of freezing-thawing resistance. The test was carried out up to 400 cycles according to KS F 2456. The compressive strength and weight of two concretes were measured and compared. As a result, the freezing-thawing resistance of steel slag concrete curing in water was almost the same with that of crushed stone concrete. But the resistance of steel slag concrete curing in air dry condition was weaker than that of crushed stone concrete. Also, the steel slag concrete which has more than 60% of W/C ratio showed much more surface degradation when compared to crushed stone concrete.

Resistance to Freezing and Thawing of Alkali-Activated Slag Concrete (알카리활성 슬래그 콘크리트의 동결융해 저항성)

  • Mun, Jae-Sung;Cho, Ah-Ram;Sim, Jae-Il;Yang, Keun-Hyeok
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2011.11a
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    • pp.105-106
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    • 2011
  • The present tests examined the resistance to freezing and thawing of alkail-activated (AA) slag concrete having compressive strength between 30~56 MPa. To enhance the compressive strength and resistance to freezing and thawing of AA slag concrete, Na ions were used for an activator. Test results revealed that the resistance to freezing and thawing of AA slag concrete is comparable to that of cement concrete when compressive strength is more than 50 MPa.

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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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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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An Experimental Study on Freezing and Thawing Characteristics of Mortar Influenced by Steam Curing Methods (증기양생방법에 따른 모르타르의 동결융해 특성에 관한 실험적 연구)

  • 장문기;박광수;김관호;이준구
    • Proceedings of the Korea Concrete Institute Conference
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    • 2001.05a
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    • pp.967-972
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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 steam curing methods 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 thawing and thawing resistance on the curing methods. The experimental results in the present study can be efficiently used to improve the characteristics of freezing and thawing resistance for concrete products carrying steam curing.

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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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