• Proceedings of the Korea Concrete Institute Conference
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• 1999.10a
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• pp.207-210
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• 1999

This experimental study was carried out to estimate the effects of mixing dosage rate and blaine on the mechanical properties of concrete admixed with ground granulated blast-furnace slag (BFS) powder. According to the test results, compressive strength of concrete admixed with slag not more than 35% was at least 80% of compressive strength of OPC concrete at 3 days age, and much bigger than that of OPC concrete at 28 days age. Consequently, in order to apply the BFS to the concrete is demanded, and rigorous construction management should be followed.

• Proceedings of the Korea Concrete Institute Conference
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• 2004.05a
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• pp.584-587
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• 2004

This research investigates the rheological behavior and the confined water ratio of the cement paste and binder condition in order to predict mix design proportion of the high flowing concrete. The purpose of this study is to determine the optimum replacement ratio of binders including fly ash, and lime stone powder by the cement weight. For this purpose, belite cement, blast furnace slag cement and ordinary portland cement are selected. As test results, the confined water ratio shows the following range ; OPC>blast furnace slag cement>belite cement. Therefore, belite cement is proved very excellent cementitious materials in a view point of the flowability. The optimum replacement ratio of lime stone powder is shown over $30\%$ in case of belite cement and about $10\%$ in case of slag cement type. Also, the optimum replacement ratio of fly ash is shown $30\%$ by the cement weight considering the confined water ratio and deformable coefficient of the paste condition.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2023.11a
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• pp.193-194
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• 2023

Recently, research is being conducted on geopolymers using industrial by-products as a cement substitute to reduce carbon dioxide emissions from the construction industry. Since geopolymers use industrial by-products, their performance varies depending on the type of alkali activator used, curing temperature, etc. Therefore, as part of a study to reduce carbon dioxide emissions from the construction industry, this study mixed blast furnace slag powder and ferronickel slag powder as cement substitutes, and compared and analyzed the fluidity and compressive strength of no-cement composites according to curing temperature.

• Journal of the Korea Institute of Building Construction
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• v.7 no.4
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• pp.101-108
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• 2007

Furnace slag powder used currently in Korea needs to add special functions in response to the increase of large-scale projects. In addition, it is advantageous in that it has a lower hydration heat emission rate than ordinary Portland cement and improves properties such as the inhibition of alkali aggregate reaction, watertightness, salt proofness, seawater resistance and chemical resistance. However, furnace slag powder is not self -hardening, and requires activators such as alkali for hydration. Accordingly, if recycled fine aggregate, from which calcium hydroxide is generated, and furnace slag, which requires alkali stimulation, are used together they play mutually complementary roles, so we expect to use the mixture as a resource-recycling construction material. Thus the present study purposed to examine the properties and characteristics of furnace slag powder and recycled aggregate, to manufacture recycled fine aggregate concrete using furnace slag and analyze its performance based on the results of an experiment, to provide materials on concrete using furnace slag as a cement additive and recycled fine aggregate as a substitute of aggregate, and ultimately to provide basic materials on the manufacturing of resource-recycled construction materials using binder and fine aggregate as recycled resources.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2021.11a
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• pp.176-177
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• 2021

In order to compensate for the defects of concrete made using only Portland cement, three-component powder mixed with blast slag and fly ash, and four-component powder concrete mixed with silica fume are being produced. When each of the admixtures is used alone, the above-described excellent performance is expressed and up to 70% of the powder is used. These technologies are also contributing to the reduction of greenhouse gases under Act on Low Carbon. Green Growth. However, calcium hydroxide is consumed as a stimulator or reaction in the case of silica fume, which causes latent hydroponicity of slag, pozzolane reaction, and silica mixtures represented by fly ash. It is known that the consumption of calcium hydroxide affects the alkalinity of concrete. As a result, the carbonation resistance is significantly lower among the durability of concrete. Research on quantification of such effects is insufficient. In this study, an experiment was conducted to quantify calcium hydroxide of the three-component and four-component powder paste using thermal analysis equipment (DTG), and the effect of the mixing amount was discussed.

• The Korean Journal of Ceramics
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• v.6 no.2
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• pp.120-123
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• 2000

The geopolymer technique may be a future-oriented technology for saving energies and resources. This technique requires 3 fundamental elements so-called filler, hardener and geopolymer liquor being generally an alkaline silicate solution. Quartz powder, water quenched granulated blast furnace slag and sodium silicate solution prepared from $Na_2O\cdot2SiO_2$were chosen for these three elements. After mixing these starting materials in appropriate proportions, monoliths were prepared by casting at room temperature. Strength tests showed the following results for 28d age speciment: 7.9-12.7 MPa in flexural strength and 20.2-32.8 MPa in compressive strength, depending on geopolymer liquor/solid ratio, P/S and fineness of the quartz powders used.

• Proceedings of the Korea Concrete Institute Conference
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• 2004.05a
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• pp.676-679
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• 2004

In this study, we considered the characteristic of drying shrinkage from age of high strength concrete with garnet minute powder to be industry by-product. The factors of experiment are unit water content$(160kg/m^3)$, water-binder ratio(30, $35\%$), fine aggregate ratio(40, 42, $44\%$), admixture replacement ratio(0, 10, $20\%$), admixture type(garnet minute powder, fly ash, blast-furnace slag). We make a comparative study of shrinkage about concrete with a passage of age(1, 3, 7, 14, 28, 56, 91 days). As a result of experiment, we reach a conclusion as follow. In the same mix condition, as unit water content and fine aggregate ratio go up, the drying shrinkage ratio increase. In the drying shrinkage ratio according to admixture replacement ratio, it goes up when admixture replacement Ratio increase in case of fly ash and blast-furnace slag. But, drying shrinkage ratio decrease when admixture replacement ratio increase in case of garnet minute powder.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2019.11a
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• pp.19-20
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• 2019

This study investigated the possibility of strength development by incorporating the slighly coarser soda-lime glass powder (GP) with 0-100 wt.% of Ground Granulated Blast Furnace Slag (GGBS) to synthesis GGBS based geopolymer. Compressive strength, water absorption & apparent porosity, were experimentally determined. To determine the homogeneity of mix, the microstructure & elemental composition of samples were studied using SEM-EDS. Study reveals the improvement in strength and reduction in porosity for the samples containing up to 30% GP. Furthermore, the microstructure analyses confirmed the development of denser and compact structure with the incorporation of glass powder up to 30%.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2015.11a
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• pp.55-56
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• 2015

In this research the processing method of Desulfurized Plaster is changed to cyclotomy, 0.3mm sieve analysis and 500℃ heat exposure, and by changing the mix rate of the binding agent to 0~20%, it was applied to mortar that used natural aggregate and blast furnace slag for testing. The test results showed that the sieve analysis and high heat exposure of the flow and air volume increased according to the increase of mixing rate of FGD while the cyclotomy decreased. The setting time accelerated as the mixing rate of FGD increased, and the compression strength increased to its maximum when the mixing rate of FGD was right around 10%, and especially showed a high trend with cyclotomy and sieve analysis.

• Journal of the Korean Ceramic Society
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• v.45 no.6
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• pp.336-344
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• 2008

Rheological properties of cement pastes containing blast furnace slag (BFS: 3,900, $7,910\;cm^2/g$) or fly ash powder (FA: 4,120, $8,100\;cm^2/g$) according to the ratio of water/binder (W/B) and the dosage of polycarboxylate type superplasticizer (PC) were investigated by a mini slump and a coaxial cylinder viscometer. In this experiment, the ratio of replacing OPC with BFS or FA was 30 wt%, the W/B was from 30 to 70 wt%. As a result, the fluidity of cement paste containing BFS or FA was improved with increasing W/B and the dosage of PC. BFS or FA replaced cement paste with W/B 70% and PC 0.3% showed the highest fluidity. The segregation range of cement paste was occurred below $10\;d/cm^2$ of the yield stress and below 50 cPs of the plastic viscosity by the coaxial cylinder viscometer. And also it was formed that the plastic viscosity and the yield stress of FA replaced cement paste were higher than them of BFS replaced cement paste.