• Proceedings of the Korean Institute of Building Construction Conference
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• 2011.11a
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• pp.215-216
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• 2011

This study investigates the effect of partial replacement with cement on the properties of blast furnace slag-based mortar. Recycled fine aggregate with various contents was used to activate the hydration of blast furnace slag in the mortar and compared its effect on strength development. Results showed that increasing cement and recycled fine aggregate increased the strength of mortar specimens. However, this study found that the mortar made with partial replacement of river sand with recycled fine aggregate of 20% developed a similar strength to the strength that cement with 10% can achieved.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2012.05a
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• pp.257-258
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• 2012

With regard to the carbon reduction that has become an international problem, we have examined the effects of compressive strength of the ground granulated blast-furnace slag mortar with the curing temperature. Also, we evaluated the mechanical properties of steel slag powder produced during the steelmaking process in order to examine the possibility as admixture.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2011.05a
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• pp.57-58
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• 2011

In the experiment, we add to NaOH, Ca(OH)₂ and Calcium Hydroxide as the Slag stimulus also mixed the cement stimulus such as NaSCN, TEA and CaCl₂ for improving compressive strenth of concrete which added the Blast Furnace Slag Powder at 1 and 3 days. In the result of strength test, It showed that 2percentage of activator 1 and 5percentage Ca(OH)₂, 1percentage of activator 3 and 5percentage of Ca(OH)₂ are higher than 100 percentage OPC.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2013.11a
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• pp.30-31
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• 2013

In this study, characteristics of the concrete replaced in large amount with blast furnace slag is analyzed by the microscopic analyses in the process of the mock-up testing to apply to the actual practice in the area of the general strength by activating a small amount of cement(25%) replaced in large amount of finely powered blast furnace slag.

• Journal of the Korean Ceramic Society
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• v.36 no.7
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• pp.725-733
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• 1999

It is a fundamental experiment to use blast-furnace slag in solidification/stabilization process. The compressive strength and leaching test of Pb and Cr doped samples were evaluated and the effects of heavy-metal ions on the hydration of slag was investigated. Sodium silicates(5wt%) was added as alkali-activator and the effects of replacing a part of slag with flyash or gypsum was also discussed. Pb ion was solidified by encapsulation of matrix. In of slag${\pm}$gypsum binder microstructure was densified by accelerating to form AFt/AFm phase and compressive strength was improved resulting in reducing leaching amount of Pb ion. Cr ion was solidified by substituting with Al ion in aluminate product. Slag+fly ash binder improved compressive strength and decreased leaching amount of Cr ion.

• Proceedings of the Korea Concrete Institute Conference
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• 2006.05b
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• pp.473-476
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• 2006

As a part of efforts to obtain high quality and economical efficiency of concrete, blast-furnace slag has been utilized by means of cement replacement. Therefore superior performance can be ensured, environmental pollution can be prevented and economical advantage can be obtained with utilization by cement replacement. But the studies on the blast-furnace slag are not systematic and reasonable. So, it was planed that basic data in regard to technique of manufacturing and economic improvement of concrete is showed with experimental comparison and investigation of Fluidity and engineering properties of concrete utilizing blast-furnace, industry by-product, as cement replacement in this study.

• Journal of Korean Society of Water and Wastewater
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• v.30 no.3
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• pp.293-297
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• 2016

This study was performed in order to obtain the effect of the compressive strength of the cured product with manufacturing conditions (amounts of fine aggregate and different types of alkali activator). Material which is the basis of the cured product was used for the blast furnace slag, which has a latent hydraulic activity. Consequently, when using sodium hydroxide as the alkali activator, it is possible to obtain a higher compressive strength than using the calcium hydroxide. And also, it can be added a 10% of fine aggregate with blast furnace slag to improve the compressive strength.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2019.11a
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• pp.25-26
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• 2019

The Reinforced concrete structure is deteriorated in durability due to various deterioration factors such as acid, salt, etc., and thus requires repair and reinforcement. In this study, compressive strength and weight change were measured by substituting blast furnace slag with excellent chemical resistance. As a result, the decrease in compressive strength decreased in proportion to the blast furnace slag substitution rate, and in the case of BFS40, the strength increased after sulfuric acid immersion. The weight change also decreased in proportion to the replacement amount.

• Geomechanics and Engineering
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• v.31 no.2
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• pp.149-158
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• 2022

Ladle furnace (LF) slag, waste from the steel-making process, was incorporated to improve the compressive strength of soil cement. LF slag was mixed to replace the cement in the soil-cement samples with wt% ratio 20:0, 15:5, and 10:10 of cement and slag, respectively. LF slag in the range of 5, 10, and 20 wt% was also separately added to the 20-wt% cement-treated soil samples. The soil-cement mixed LF slag samples were incubated in a plastic wrapping for 7, 14, and 28 days. The strength of soil cement was highly developed to be higher than the standard acceptable value (0.6 MPa) after incorporating slag into soil cement. The mixing of LF slag resulted in more hydration products for bonding soil particles, and hence improved the strength of soil cement. With the LF slag mixing either a replacement or additive materials in soil cement, the LF slag to cement ratio is considered to be less than 1, while the cement content should be more than 10 wt%. This is to promote a predominant effect of cement hydration by preventing the partially absorbed water on slag particles and keeping sufficient water content for the cement hydration in soil cement.

• Journal of Korean Society of Environmental Engineers
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• v.29 no.7
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• pp.810-819
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• 2007

Investigation of alkali activation of fly ash and blast furnace slag was carried out using waterglass and sodium hydroxide. XRD, FTIR, $^{29}Si$ and $^{27}Al$ NMR, TGA and SEM were used to observed the reaction products and microstructure of the fly ash/slag cement (FSC) pastes. The reaction products were amorphous or low-ordered calcium silicate hydrate and aluminosilicate gel produced from alkali activation of blast furnace slag and fly ash, respectively. On the basis of this investigation, waterglass solution with a modulus(Ms) of 1.0 and 1.2 is recommended for alkali activation of fly ash and blast furnace slag. Morphology of FSC pastes alkali-activated with Ms of 1.0 and 1.2 shows a more solid and continuous matrix due to restructuring of gel-like reaction products from alkali-activated fly ash and blast furnace slag together with another hydrolysis product(i.e., silica gel) from water glass.