• Proceedings of the Korean Institute of Building Construction Conference
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• 2012.11a
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• pp.19-21
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• 2012

This paper was to investigate the effect of incinerator ash on engineering properties of the high volume blast furnace slag concrete through Mock-up test. Test results revealed that the use of recycled aggregates resulted in increase of slump compared with the OPC concrete. But, the use of recycled aggregates did not affect the results of air contents and chloride contents. The use of recycled aggregates showed shortening of setting time of high volume blast furnace slag concrete. When the recycled aggregate was used, delay in strength development at early age happened with high volume blast furnace slag concrete compared with that of OPC concrete.

• Journal of the Korea Concrete Institute
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• v.17 no.3 s.87
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• pp.473-480
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• 2005

In this study, a mix design for self compacting concrete was based on Okamura's method and concrete incorporated just a ground granulated blast furnace slag. Replacement ratio of slag is in the range of $20-80\%$ of cement matrix by volume. For the optimal self compactability in mixture incorporating ground granulated blast furnace slag, the paste and mortar tests were first completed. Then the slump flow, elapsed time of 500mm slump flow, V funnel time and filling height by U type box were conducted in concrete. The volume of coarse aggregate in self compacting concrete was in the range of $50-60\%$ to the solid volume percentage of coarse aggregate. Finally, the compressive and splitting tensile strengths were determined in the hardened self compacting concrete incorporating ground granulated blast furnace slag. From the test results, it is desirable for self compacting concrete that the replacement of ground granulated blast furnace slag is in the range of $40-60\%$ of cement matrix by volume and the volume of coarse aggregate to the solid volume percentage of coarse aggregate with a limit of $55\%$.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2013.05a
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• pp.35-36
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• 2013

Electric arc furnace oxidizing slag from massively produced steel slag has been used in road bases and subbases, hot mix asphalt, and landfill. Electric arc furnace oxidizing slag contains iron (15%~30%) and has a high density of 3.0~3.7 ton/m3. Depending on the type and amount of concrete aggregates, the radiation-shielding characteristics can vary. Therefore, aggregates of electric arc furnace oxidizing slag can be considered for the production of radiation-shielding concrete. The experimental design of this study is experiments on Compressive strength experiments, X-ray irradiation experiments, and experiments related to the unit volume weight were carried out on hardened concrete. This experiment compared the performance evaluation of radiation shielding of concrete using electric arc furnace oxidizing slag.

• Proceedings of the Korea Concrete Institute Conference
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• 2003.11a
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• pp.48-53
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• 2003

The steel slag, a by-product which is produced on the process of manufacturing steel by refining pig iron is mainly used as road materials after aging it. It is necessary to age steel slag for long time in air because the reaction with water and free-CaO in steel slag could make the volume expanded. Due to this reason it prevents steel slag from being used as aggregate of concrete. But steel slag used in this study is controled by a air-jet method which rapidly cools substance melted at a high temperature. Rapid cooling prevents from generating of free-CaO in steel slag. In this study, it was investigated that steel slag manufactured by air-jet method affects on concrete in the freezing and thawing. As results of this study, concrete mixed with steel slag was worse in the freezing and thawing than concrete mixed with sand in spite of using air entraining agent. To obtain durability of concrete in the freezing and thawing, it is desirable to mix 50% of steel slag in concrete per unit weight of volume.

• Proceedings of the Korea Concrete Institute Conference
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• 2004.11a
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• pp.751-754
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• 2004

There are many factors that affect on the flowing properties of high flowing concrete(HFC), which are fluidity, compactibility, non-segregation ability and fillingability. And because the aggregate which is one of the factors occupies high volume in concrete, it has a much effect on the properties of high flowing concrete according to its size, quality and quantity etc. This is an experimental study to analyze the effect of admixture and volume of coarse aggregate in concrete on the flowing properties of high flowing concrete. For this purpose, the kinds of admixture are fly-ash and blast furnace slag. Also volume of coarse aggregate in concrete are 280, 290, 300, 310, 320 $(\ell/m^3)$. The test of flowablity properties is slump-flow, Air content, V-lot, L-Flow. According to test results, it was found that the compactibility of HFC is more superior to use blast furnace slag than other, and according .to kind of admixture, most compatible volume of coarse are different. Also when used blast furnace slag, the volume of coarse are increased than used fly-ash.

• KCI Concrete Journal
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• v.11 no.3
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• pp.19-28
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• 1999

This study treated self-compacting high Performance concrete as two Phase materials of Paste and aggregates and examined the effect of powder and aggregates on self-compacting high performance, since fluidity and segregation resistance of fresh concrete are changed mainly by paste. To improve the fluidity and self-compactibility of concrete, optimum powder ratio of self-compacting high performance concrete using fly ash and blast-furnace slag as powders were calculated. This study was also designed to provide basic materials for suitable design of mix proportion by evaluating fluidity and compactibility by various volume ratios of fine aggregates, paste, and aggregates. As a result, the more fly ash was replaced, the more confined water ratio was reduced because of higher fluidity. The smallest confined water ratio was determined when 15% blast-furnace slag was replaced. The lowest confined water ratio was acquired when 20% fly ash and 15% blast-furnace slag were replaced together. The optimum fine aggregates ratio with the best compactibility was the fine aggregate ratio with the lowest percentage of void in mixing coarse aggregate and fine aggregate In mixing the high performance concrete. Self-compacting high performance concrete with desirable compactibility required more than minimum of unit volume weight. If the unit volume weight used was less than the minimum, concrete had seriously reduced compactibility.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2015.05a
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• pp.44-45
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• 2015

Although the carbonation problem of high-volume slag concrete has been solved by the mixed use of emulsified refine cooling oil as the pilot study, there was an instance of securing air quantity and frost resistance followed by the use of Expancel due to the problem of having vulnerability in frost resistance in result as the air quantity has not been secured. But due to the problem of Expancel not being economical, air quantity and frost resistance of high-volume slag concrete mixed with ERCO are attempted to be secured using micro bubble that can remain in the water for a long time as a relatively economical and very microscopic bubble.

• Proceedings of the Korea Concrete Institute Conference
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• 2002.10a
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• pp.567-572
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• 2002

This research investigates experimentally an effect on the quality performances of the high flowing concrete according to binder types. The purpose of this study is to determine the optimum mix proportion of the high flowing concrete having good flowability, viscosity and no-segregation. For this purpose, two types using belite cement＋lime stone powder(LSP) and furnace slag cement+lime stone powder are selected and tested by design factors including water cement ratio, fine and coarse aggregate volume ratio. As test results of this study, the optimum mix proportion for binder types is as followings. 1) One type based belite cement ; water cement ratio $51^{\circ}C$, fine aggregate volume ratio $43^{\circ}C$ and coarse aggregate volume ratio $53^{\circ}C$, replacement ratio of LSP $42.7^{\circ}C$. 2) Another type based slag cement : water cement ratio $41^{\circ}C$, fine aggregate volume ratio $47^{\circ}C$ and coarse aggregate volume ratio $53^{\circ}C$, replacement ratio of LSP $13.5^{\circ}C$.

• Journal of the Korean Recycled Construction Resources Institute
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• v.2 no.3
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• pp.239-246
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• 2014

High volume slag concrete is attracting new attention and are thought to have promising potential for industrial applications, partly due to the climate debate, but especially due to their very low heat of hydration and their good durability in chemically aggressive environments. However, High volume slag concretes tend to have slower strength development especially. In this study, the effect of anhydrite ($CaSO_4$) on the mechanical and durability performance of high volume slag concrete were investigated. The main variables were anhydrite contents (0, 4, 6, 8, 10%). Test results show that 4~8% anhydrite concrete have improved engineering properties (hydration, compressive strength, shrinkage, creep, carbonation) as control concrete at early ages.

• 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.