• International Journal of Concrete Structures and Materials
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• v.5 no.2
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• pp.125-131
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• 2011

Five all-lightweight alkali-activated (AA) slag concrete mixes were tested according to the variation of water content to examine the significance and limitation on the development of cementless structural concrete using lightweight aggregates. The compressive strength development rate and shrinkage strain measured from the concrete specimens were compared with empirical models proposed by ACI 209 and EC 2 for portland cement normal weight concrete. Splitting tensile strength, and moduli of elasticity and rupture were recorded and compared with design equations specified in ACI 318-08 or EC 2, and a database compiled from the present study for ordinary portland cement (OPC) lightweight concrete, wherever possible. Test results showed that the slump loss of lightweight AA slag concrete decreased with the increase of water content. In addition, the compressive strength development and different mechanical properties of lightweight AA slag concrete were comparable with those of OPC lightweight concrete and conservative comparing with predictions obtained from code provisions. Therefore, it can be proposed that the lightweight AA slag concrete is practically applicable as an environmental-friendly structural concrete.

• Proceedings of the Korea Concrete Institute Conference
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• 2003.11a
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• pp.120-123
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• 2003

In order to evaluate the applicability of steel slag aggregates for tetrapod concrete, the properties of concrete as structural material were investigated. The biochemical research of marine concrete using steel slag aggregates was also carried out. The tested concrete properties are slump, air content, compressive strength, splitting tensile strength, elastic modulus, carbonation, hydration heat, freezing and thawing, sulfate attack, drying shrinkage, etc. The biochemical experiments are carried to research the propagation and reproduction of seaweeds and survival of bottom dwelling species. According to the experimental results, the steel slag aggregate content did not have a significant effect on compressive strength, splitting tensile strength and elastic modulus. The durability of concrete was not influenced by the steel slag aggregate content. From the biochemical research, steel slag aggregate can be evaluated as the material that is ideally suited for promoting propagation and reproduction of seaweeds and survival of bottom dwelling species.

• Proceedings of the Korea Concrete Institute Conference
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• 2004.05a
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• pp.672-675
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• 2004

The objective of this study was to understand the effect of hwangtoh and slag on various properties of concrete. Main variables were replacement level of admixtures, hwangtoh and slag, and curing temperature. Test results indicated that the compressive strength of concrete replaced by either hwangtoh and slag was significantly influenced by curing temperature. The elasticity modulus and compressive peak strain of concrete showed a small increase with increasing hwangtoh replacement.

• Proceedings of the Korea Concrete Institute Conference
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• 1997.10a
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• pp.65-68
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• 1997

In this study, we investigate the difference between natural aggregate and electric arc furnace (EAF) slag one in order to use EAF slag aggregate as coarse aggregate in concrete. We find the physical and chemical properties of EAF slag aggregate according to the different aging processes. We consider the properties of the concrete made with EAF slag aggregate on these bases.

• Proceedings of the Korea Concrete Institute Conference
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• 2006.05a
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• pp.522-525
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• 2006

This study is intended to discuss the application of blast slag for concrete to improve the durability of precast concrete box culvert. The precast concrete box culverts with blast slag are tested to verify the effect of early strength. The results show that the initial cracking load and yielding load of the blast slag concrete members are increased when they are compared with those of the normal concrete. In the prototype precast concrete box culvert experiment, initial crack control effect and ductility index are increased. It can be concluded that the use of blast slag was improved the durability in precast concrete box culvert.

• Journal of the Korea Concrete Institute
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• v.12 no.5
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• pp.59-68
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• 2000

A series of experiments were performed to investigate the strength characteristics of concrete which contain air cooled blast-furnace slag as coarse aggregate. The slag is a by product of GISC. The experimental conditions are varied with three different W/C(45%, 50%, 55%) and the weight of water and S/a are constant. The strength properties of the concrete at 7days, 28days, 90days are examined. Also the same strength properties are examined for the normal concrete which contain river gravel and crushed stone respectively as coarse aggregate. As the comparison results of the strength properties, it was found that the compressive strength development of concrete containing blast-furnace slag is better than that of concrete using river gravel at early age, however this is adversely at long-term age, and the tensile and flexural strength of the concrete were not nearly affected by water-cement ratio.

• Magazine of the Korea Concrete Institute
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• v.6 no.4
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• pp.113-122
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• 1994

To examine the applicabilty of the converter furnace slag from iron-works as concrete aggregate respective concrete furnace slag with contents of 20%. 40%, 60%. 80% were mixed with granulated slag, and the strength and stability tests for these specimens were followed. The slump value of the concrete mixed with converter furnace slag was higher than that of the conventional concrete. Furnace slag and granulated slag was increased as the increase of converter furnace content. The strength of the concrete mixed with converter furnace slag and granulate slag increased as an increase of converter furnace content and age. The expansion rate of the concrete mixed with converter furnace slag and granulated slag increased from 0.007% to 0.19% as the converter furnace content changed from 20% to 80%. From the above results in the strength and expansion rate, the concrete with the converter furnace content of 40% was considered to be recommandable for the stable construction of the concrete. Calculated formulas for tensile strength(${\sigma}_t$) and flexural strength(${\sigma}_f$) from the regression a.nalysis of the correlations among these compressive strength (${\sigma}_c$), tensile strength and flexural strength are as follows. ${\sigma}_t$ = 0.16952${\sigma}_c$ - 4.9313 ${\sigma}_f$ = 0.25727${\sigma}_c$ + 6.0528

• Proceedings of the Korea Concrete Institute Conference
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• 2001.11a
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• pp.629-634
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• 2001

Recently, to consider financial and constructive aspect, usage of Admixture, like Blast-Furnace Slag and Fly-Ash, are increased. Also the use of cold-weather-concrete is increased. Blast-furnace Slag, a by-product of steel industry, have many advantage, to reduce the heat of hydration, increase in ultimate strength and etc. But it also reduces early-age strength, so it is prevented from using of Blast-Furnace Slag at cold-weather-concrete. In this study, for the purpose of increasing usage of Blast-Furnace Slag at cold-weather-concrete, it is investigated the strength properties of concrete subjected to frost damage for the cause of early age curing. According to this study, if early curing is carried out before having frost damage, the strength of concrete, subjected to frost damage, is recovered. And that properties is not connected with the frost cause.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2023.11a
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• pp.147-148
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• 2023

Recently, as blast furnace slag concrete has become widely used, managing the strength of concrete has become important. mSn is a method of correcting the difference in strength between standard cured specimens and concrete exposed to changes in temperature. In this study, the predicted strength based on the maturity of the central and outer parts of the blast furnace slag concrete structure is compared with the actual strength measured through coring. As a result, the actual strength difference between the center and the outer part of the concrete mixed with blast furnace slag was larger than the predicted strength difference.

• Proceedings of the Korea Concrete Institute Conference
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• 1995.04a
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• pp.30-35
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• 1995

This paper presents fundamental experiment for the properties of high performance concrete in its fresh and hardened state made with ground granulated blast-furnace (GGBF) slag. The result is that the effect of decreasing xoncrete temperature is to the mixing ratio of GGBF slag, but it presents disadvantage in the slump loss phase. In addition to, we know that the splitting tensile strength, compressive strength and elastic modulus of concrete mixed with high fineness GGBF slag are increased at age 28days.