• Title/Summary/Keyword: Freezing and Thawing Resistance

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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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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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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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Void Ratio, Compressive Strength and Freezing and Thawing Resistance of Natural Jute Fiber Reinforced Non-Sintering Inorganic Binder Porous Concrete (자연마섬유보강 비소성 무기결합재 다공성 콘크리트의 공극률, 압축강도 및 동결융해저항성 평가)

  • Kim, Hwang Hee;Kim, Chun Soo;Jeon, Ji Hong;Park, Chan Gi
    • Journal of The Korean Society of Agricultural Engineers
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    • v.57 no.2
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    • pp.67-73
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    • 2015
  • This study evaluated the effects of fibers on the void ratio, compressive strength and repeated freezing and thawing resistance of porous vegetation concrete with binder type (non-sintering inorganic binder and blast furnace slag cement) and natural jute fiber volume fraction (0.0 %, 0.1 % and 0.2 %). The natural jute fiber volume fraction affected the void ratio, compressive strength and repeated freezing and thawing resistance. Added of natural jute fiber resulted in improved properties of the void ratio, compressive strength and freezing and thawing resistance. Also, the both compressive strength and freezing and thawing resistance increased with natural jute fiber volume fraction up to 0.1 % and then decreased with fiber volume fraction at 0.2 %.

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.

Corrosion of Steel in Concrete Deteriorated by Freezing/Thawing and Carbonation (동결융해 및 중성화를 받은 콘크리트의 철근 부식 특성)

  • 정해문;김종우;이대근;최광일
    • Proceedings of the Korea Concrete Institute Conference
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    • 1997.10a
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    • pp.293-298
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    • 1997
  • Corrosion of steel reinforcing in concrete deteriorated by freezing/thawing and carbonation was characterized. Concrete specimens were prepared using various kinds of cements such as ordinary portland cement (type I), low heat portland cement (type IV, belite rich cement), sulphate resistance portland cement (type V), blast furnace slag portland cement and ternary blended cement. Of various cements, type V and type IV with lower $C_3A$ content revealed better steel corrosion resistance after freezing/thawing and carbonation. $C_3A$ content in cement might affect freezing/thawing resistance in sea water.

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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.

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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