• Proceedings of the Korea Concrete Institute Conference
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• 1998.10c
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• pp.19-24
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• 1998

In this study, blended cement with low blaine(2000, 3000$\textrm{cm}^2$/g) blast-furnace slag power by 10-70wt.% was investigated through the measurement hydration heat, physical properties. The experiment results indicated compressive strength was decreased as low blaine slag blended, but hydration heat was reduced significantly and flow of the cement paste was increased.

• Journal of the Korea Institute of Building Construction
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• v.14 no.4
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• pp.285-291
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• 2014

Partial replacement of cement with blast furnace slag has many advantages such as the reduction of construction fee, the decrease of hydration heat and the increase of long-term strength. Hence, slag is widely used in practice. This study investigates the effect of slag on the rheological properties of cement paste and mortar. Three different types of slag (BS1, BS2 and BS3) with five different contents (0, 20, 40, 60 and 80 wt.%) were used to replace the cement. Each type of slag has different fineness. Water to binder ratio was 0.5. Test results showed that the partial replacement of BS1 and BS2 decreased flow and increased O-lot flow time, whereas that of BS3 caused an opposite effect, i.e., increased flow and decreased O-lot flow time. It was found that there was a good corelation between the values of yield stress and flow.

• Journal of the Korean Ceramic Society
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• v.55 no.1
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• pp.61-66
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• 2018

In this study, fabrication method of inorganic insulation were studied to reduce $CO_2$ from buildings. Main materials for inorganic insulation were used cement, blast furnace slag and aluminum powder as foaming agent. Mixing ratio of cement and slag was controlled and physical properties of inorganic insulation were analyzed. When inorganic insulation was fabricated using cement and slag, expanded slurries were not sunken and hardened normally. Pore size was 0.5 - 2 mm; mean pore size was about 1mm in inorganic insulation. Compressive strength of inorganic insulation increased with curing time and increased slightly with cement fineness. However, specific gravity decreased slightly with curing time; this phenomenon was caused by evaporation of adsorptive water. When inorganic insulation was dried at $60^{\circ}C$, compressive strength was higher than that of undried insulation. The highest compressive strength was found with a mixture of cement (50%) and slag (30%) in inorganic insulation. Compressive strength was 0.32 MPa, thermal conductivity was 0.043 W/mK and specific gravity was $0.12g/cm^3$.

• The Journal of Engineering Geology
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• v.30 no.4
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• pp.541-555
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• 2020

The grouting method is used for reinforcing and waterproofing the soft ground, increasing the bearing capacity of structures damaged by lowering or subsidence due to rise and vibration, and for ordering. This study attempted to develop a blast furnace slag-based cementless grout material to increase the strength and hardening time of the grout material using reinforcing fibers. In this regard, in this study, it was used in combination with calcium hydroxide, which is an alkali stimulant of the three fine powders of blast furnace slag, and the content of calcium hydroxide was used by substituting 10, 20, and 30% of the fine powder of blast furnace slag. In addition, in order to compare the strength according to the presence or absence of reinforcing fibers, an experiment was performed by adding 0.5% of each fiber. As the content of carbon fibers and aramid fibers increased, the uniaxial compressive strength increased, and it was confirmed that the crosslinking action of the fibers in the grout material increased the uniaxial compressive strength. In addition, it was confirmed that the gel time sharply decreased as the content of the alkali stimulate increased.

• 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.

• 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%.

• Journal of the Korea Institute of Building Construction
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• v.20 no.1
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• pp.27-34
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• 2020

In the industry, due to the carbon dioxide gas produced during cement production is increasing, research on recycling by-products has been actively conducted. In the industrial by-products, the high calcium fly ash(HCFA) produced by the blast-furnace in the circulating fluidized bed combustion method has a high ratio of CaO and CaSO4. In view of this, the purpose of this is to use high calcium fly ash(HCFA) as a stimulant in blast furnace slag powder and use it as a cement substitute. As a result, it is judged that the substitution ratio of HCFA should be 15% or less. In addition, although durability and strength are relatively lower than of OPC, it is considered that it can be utilized as an environmentally building material.

• Journal of the Korean Recycled Construction Resources Institute
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• v.1 no.2
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• pp.107-113
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• 2013

This study is the study desiring to solve the problem by utilizing the kinds of recycled resources considered to be troubled complementarily. Namely the reaction of potential hydraulicity of Blast Furnace Slag Powder (BS) shall be reacted with the alkali of Recycled Fine Aggregates Coarse Aggregate, it has been experimented to obtain the optimum value with the replacement ratio of incineration plant ash (WA) treated with the slaked lime as the experiment variable by solving the alkali of shortage with the Ordinary Portland Cement (OPC). As a result, the liquidity and the air volume are declined slightly as the replacement ratio of incineration plant ash WA increases, the mixture of incineration plant ash WA 1% has been analyzed to be the most suitable considering the viewpoint of effective handling of waste as the compression and the tensile strength showed the maximum value before and after 1% even though it was disadvantageous with the increase of chloride content.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2013.05a
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• pp.37-38
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• 2013

The fine powder obtained from the manufacturing process of recycled coarse aggregate contains unhydareted cement particles on their surface. It is believed that the alkalinity of the powder (11.0-12.5) is enough to active the slag-based composites. In this paper, the obtained powder was sieved and divided into two sizes, i.e., 0.08 mm and 0.3 mm, and added to the slag-based mortar. Results showed that the fine powder had an effect on the slump and the compressive strength of slag-based composites. With the different pH values of the powder, it could be seen that the distance between the two level powders. And found the peak 28 days compressive strength as the replacement ratio of the recycled aggregate powder changed. The findings from this study provide an indication that with achieved compressive strength, the fine powder can be used in a light weight concrete.

• Journal of the Korea Concrete Institute
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• v.18 no.6 s.96
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• pp.769-776
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• 2006

Recently, owing to the development of industry and the improvement of building techniques, concrete structures are becoming larger and higher. In hardening of these large connote structures, the heat of hydration gives rise to considerable thermal stress depending on the size and environmental condition of concrete, which might cause thermal cracking. Especially, the crack may cause severe damage to the safety and the durability of concrete structure. This study investigates the thermal properties of concrete according to several binder conditions, such as OPC, Belite rich cement(BRC), slag cement(SC), blast furnace slag(B) added cement fly ash(F) added cement and blast-furnace-slag and fly ash added cement. As a result of this study, the properly of concrete is most better BRC than others, and fly ash(25%) added cement and BFS(35%)-fly ash(15%) added cement gets superior effect in the control of heat hydration. But synthetically considered properties of concrete, workablity, strength heat hydration, etc, it is more effective to use mineral admixture. Especially, to be used Blast Furnace slag is more effective.