• Journal of the Korean Society of Safety
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• v.12 no.1
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• pp.101-107
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• 1997

High strength concrete(HSC) using high range water reducing admixture (HRWR) has the defect which severe slump loss occurs according to elapsed time. For using HSC without any trouble, special caution and countermeasure against this problem are necessary. In this study, for minimizing the slump loss of HSC, mineral admixture( flyash, ground granulated blast furnace slag ) and gypsum were used experimentally. Flyash and ground granulated blast furnace slag are effective in reducing the slump loss of HSC. Especially, the slump loss of HSC containing mineral admixture and gypsum Is minimized by the aggregation inhibiting action of gypsum. Cement substituted with flyash 30% or ground granulated blast furnace slag 50% by weight are very effective in minimizing the slump loss.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2016.10a
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• pp.102-103
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• 2016

Recently on construction sites, there is increased use of concrete with large quantities of blast-furnace slag(BS) admixture replacements, for purposes of reducing CO2 created from cement, one of the ingredients of concrete. But such high-BS fineness changes can have a huge effect on the quality of mortar and concrete. Therefore in this study an experiment was conducted in which liquidity and intensity of mortar depending on an artificially-applied change in fineness degree at degree 7. The results, though subtle, were that the larger the fineness degree, liquidity increased and air quantity decreased, and compression and flexural strength increased.

• Journal of The Korean Society of Agricultural Engineers
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• v.55 no.3
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• pp.123-128
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• 2013

This study was performed to evaluate the slump flow, air content, setting time, compressive strength, adiabatic temperature rise and diffusion coefficient of chloride used ordinary portland cement, crushed coarse aggregate, crushed sand, river sand, fly ash, limestone powder, blast furnace slag powder and superplasticizer to find optimum mix design of low carbon green concrete for structures. The performances of low carbon green concrete used fly ash, limestone powder and blast furnace slag powder were remarkably improved. This fact is expected to have economical effects in the manufacture of low carbon green concrete for structures. Accordingly, the fly ash, limestone powder and blast furnace slag powder can be used for low carbon green concrete material.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2014.11a
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• pp.146-147
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• 2014

The environmental pollution problem the globally related to global warming arises, the demand for the solar power generation increases. But is generated sludge about 2tons in order to produce 1ton in the solar power generation used main material polysilicon. In this way, the arising sludge there is not method recycling and it is all discarded. Therefore, in this research, cement is not used dynamic properties tries to be analyze inorganic binder based on blast furnace slag and polysilicon sludge ratio. The appropriate replacement ratio of the experimental result polysilicon sludge was to be 8%.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2009.05b
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• pp.97-100
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• 2009

This study is a basic experiment to complement the problems in decrease of strength in case we change lots of fly ash("FA" here in after) in ordinary portland cement("OPC" here in after). Mixing plaster that is known to be effective in improvement in hydration of blast furnace slag powder("BS" here in after). After FA changed concrete is mixed, the study physical proporties such as compression strength, increased proportionaly. When second-class BS 5 % and gypsum 2 % changed, compare to OPC strength approximately 120 % was recorded after one day. In FA 20 % case, according to the ratio of gypsum changed results showed similar trend, but compared to FA 10 % changed concrete, expression strength improvement was lower.

• Advances in concrete construction
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• v.5 no.5
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• pp.437-450
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• 2017

The present work investigates about the development of a novel construction material by utilizing Granulated Blast Furnace Slag (GBS), an industrial waste product, as substitution of natural fine aggregates. For this, experimental work has been carried out to determine the influence of GBS on the properties of concrete such as compressive strength (CS), modulus of elasticity, ultrasonic pulse velocity (UPV), chloride penetration, water absorption (WA) volume of voids (VV) and density. Concrete mixes of water/cement (w/c) ratios 0.45 and 0.5, and incorporating 20%, 40% and 60% of GBS as partial replacement of natural fine aggregate (sand) are designed for this study. The results of the experimental investigation depict that CS of concrete mixes increases with the increasing percentages of GBS. Moreover, the decrease in chloride penetration, WA and VV, and improvement in the modulus of elasticity, UPV, density of concrete is reported with the increasing percentage of GBS in concrete.

• Geomechanics and Engineering
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• v.19 no.4
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• pp.361-368
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• 2019

This study aims to evaluate the applicability of a grout material that is mixed with carbon fiber, biogrout, ground granulated blast furnace slag (GGBS) powder and cement. Uniaxial compressive strength tests were performed on homo-gel samples at days of 1, 3, 7, 14 and 28. In addition, the variation of permeability with the mixing ratios was measured. Based on the uniaxial compressive strength test, it was confirmed that the uniaxial compressive strength increased by 1.2times when carbon fiber increased by 1%. In addition, as a result of the permeability test, it was found that when the GGBS increased by 20%, the permeability coefficient decreased by about 1.5times. Therefore, the developed grout material can be used as a cutoff grouting material in the field due to its strength and cut-off effect.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2021.11a
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• pp.101-102
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• 2021

The compressive strength of concrete is greatly affected by the temperature inside the concrete at the initial age immediately after pouring. The apparent activation energy of cement and the setting time of concrete are major factors influencing the development of compressive strength of concrete. This study measured the apparent activation energy and setting time according to the change in W/B for each mixing rate of Ground Granulated Blast-Furnace Slag (GGBFS). And after calculating the compressive strength prediction model, the accuracy of the prediction model was evaluated by comparing the predicted compressive strength and the compressive strength.

• Journal of The Korean Society of Agricultural Engineers
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• v.55 no.2
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• pp.59-64
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• 2013

The present study is to evaluate physical and mechanical properties of porous concrete having non cement that mainly causes carbon emission. This study aims to explore eco-friendly concrete technology capable of reducing the amount of carbon emission due to the use of normal cement by substituting it with non cement porous concrete to which alkali-activator and blast-furnace slag powder are impregnated. As experimental variables, 5 %, 6 %, 7 %, 8 %, 9 % and 10 % of alkali-activator were substituted as binders and applied. Testing evaluated in this study were pH value, void ratio, compressive strength and residual compressive strength shown after being immersed in $H_2SO_4$ solution and $Na_2SO_4$ solution. The test results were compared with those tested with the use of porous concrete to which 400 $kg/m^3$ of unit cement amount was applied as binder. In consequence, it was concluded that; as for pH value, it was decreased than was the case in which cement was used, but increased with the more the use of alkali activator; as for void ratio and compressive strength, the mix proportion in which 9 % and 10 % of alkali activator were applied in terms of substitution ratio showed the result similar to the mixture in which 400 $kg/m^3$ of unit cement ratio was applied; and, as for residual compressive strength in the case of being immersed in $H_2SO_4$ solution and $Na_2SO_4$ solution, the compressive strength was increased, thus leading to improved chemical resistance.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2003.05a
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• pp.9-12
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• 2003

High flowing concrete has not spread whole in the normal concrete structure, because it requires special quality control technique. And recently owing to the lack of natural resources and reinforcement of environmental standard, the construction cost of cement is increased rapidly. Also remicon industry has gone through various economical difficulty as the manufacture cost of concrete is increased. So, the purpose of this study is to evaluate the qualities of middle fluidity concrete using the fly-ash and portland blast-furnace slag cement in order to decrease the amount of cement and resolve the problem of the quality control of high flowing concrete and the manufacture cost. The results of this study show that it reduce the amount of addition of superplasticizer and develope properties of concrete to the use the fly-ash and portland blast-furnace slag cement.