• Proceedings of the Korean Institute of Building Construction Conference
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• 한국건축시공학회 2022년도 봄 학술논문 발표대회
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• pp.192-193
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• 2022

In this study, concrete durability was reviewed before CGS, a by-product generated from IGCC, was used as a fine aggregate for concrete. The characteristics of concrete and effect on carbonization according to the type of pre-mixed cement and the CGS substitution rate were analyzed. As a result of the analysis, the depth of carbonation according to the pre-mixed cement types increased by up to 52%, and the carbonation resistance tended to be similar overall when CGS was used as a fine aggregate.

• Journal of the Korean Wood Science and Technology
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• 제22권2호
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• pp.37-45
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• 1994

The possibility of reusing the paper sludge as a raw material of composition board mixed with cement was investigated. For the measurement of physical and mechanical properties, wood coment board and sludge combinend cement boards were fabricated with the three weigh ratios of paper sludge 10 % (SI), 20 % (S II) and 30 % (S III) to cement weight. For adding the cement hardning, $CaCl_2$ was also added to each mixed paste with the ratio of 1 %, 3 % and 5 % to cement weight, respectively. Crystal formation in paper sludge-, wood-cement composites was observed by scanning electron microscope. The results were summarized as follows. 1. Density and partial compressive strength of each specimens were relatively high in the order of sludge I, sludge II, Korean pine, Italian poplar and sludge III, sludge I, Korean pine, sludge II, Italian poplar and sludge III. 2. The mechanical properties of sludge-cement boards (S I and II) were higher than that of wood-cement boards prepared with Korean pine and Italian poplar. But the mechanical properties of wood-cement boards were improved by the adding of $CaCl_2$. 3. Water absorption and thickness swelling were increased with increase of sludge content to cement weight. 4. In SEM observation, sludge-cement composites showed sufficiently formed crystals but wood-cement composites showed poorly formed crystals.

• Journal of the Korean Ceramic Society
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• 제33권8호
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• pp.889-894
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• 1996

This study was subjected to the stabilization of heavy metals using DSp cement. Heavy metal Cr and Pb ions were mixed with cement paste and hydration behavior and leaching property by heavy metal were exami-ned. It was found that, Cr ion accelerated the early hydration of the cement and has no accelerating effect in later hydration period. However Pb ion retarded the hydration of the cement for a early hydration periods. As a result of leaching test the quantity of leachant has a very low value and the influence of leached heavy metal effected on the environments is very weak.

• Proceedings of the Korea Concrete Institute Conference
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• 한국콘크리트학회 2005년도 봄학술 발표회 논문집(I)
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• pp.487-490
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• 2005

This study was performed to investigate the effect of ternary blended cement concrete mixed with slag cement and fly ash on the compressive strength, the resistance to chloride ion penetration and reduction of hydration heat. Each performance of ternary blended cement concrete compared with binary blended cement concrete and ordinary portland cement concrete. As a result, it was concluded that ternary blended cement concrete is suitable to mass concrete under marine environment.

• Journal of the Korean Ceramic Society
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• 제27권8호
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• pp.1034-1042
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• 1990

Investigation for the preparation of high strength hardened cement paste using ordinary portland cement, hydroxypropyl methyl cellulose(HPMC) with various admixtures was carried out. The cement paste was mixed with 0.1 of water cement ratio by twin roll mill and cured 60 days in humidity chamber. When the quartz powder or white cement was added to the paste, the flexural strength was 900∼1000kg/㎠ and the Young's modulus was 8∼9×105kg/㎠. When the silicafume was added, the flexural strength was 800kg/㎠ and the Young's modulus was 6×105kg/㎠.

• Proceedings of the Korea Concrete Institute Conference
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• 한국콘크리트학회 2003년도 가을 학술발표회 논문집
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• pp.505-508
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• 2003

The rheological properties of cement paste system mixed with mineral admixture for the purpose of increasing the strength and improving durability and rheology of concrete were investigated. The results were as follows: The rheological properties of one-ingredient paste system were improved with increasing the dosage of superplasticizer. For two-ingredients paste system, increasing the replacement rate of BFS(blast furnace slag) and FA(fly ash), the yield value and plastic viscosity were decreased compared with non-replacement. In the OPC(ordinary portland cement)-SF(silica fume) system, increasing the replacement rate of SF, the plastic viscosity and yield value increased linearly. In three-ingredients paste system, both OPC-BFS-SF and OPC-FA-SF system, the rheological properties were improved compared with the only replacement of SF. Both two- and three- ingredients paste system, the rheological properties using BFS were improved more than FA.

• Proceedings of the Korean Institute of Building Construction Conference
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• 한국건축시공학회 2022년도 봄 학술논문 발표대회
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• pp.154-155
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• 2022

In this study, propose a plan to efficiently utilize CGS, a by-product generated from IGCC, as a mixed fine aggregate for concrete. The effect of the premixed cement types and CGS replacement rate on the overall characteristics and length change rate of concrete was analyzed. As a result of the analysis, the effect of CGS was found to be insignificant, and the effect of cement was found to be dominant.

• Proceedings of the Korean Institute of Building Construction Conference
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• 한국건축시공학회 2020년도 봄 학술논문 발표대회
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• pp.179-180
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• 2020

CO2 emissions are caused by cement manufacturing process. To solve this problem construction industry are using industrial by-products to replace cement. In this study, three different industrial by products were used and mixed with hybrid fibers to enhance bond strength. As the result, Regardless of the mixing rate of silica fume, the compressive strength of the ternary non cent mortar was higher than that of OPC and binary. And mixed hybrid fibers cured by room temperature compressive strength were 23% higher than those without hybrid fibers.

• Proceedings of the Korea Concrete Institute Conference
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• 한국콘크리트학회 1996년도 봄 학술발표회 논문집
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• pp.166-171
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• 1996

This study examines whether the raw diatomaceous rock, after thermally activated for converting into a pozzolanic form, can improve cement quality(i.e., compressive strength) of the cement-mortar. The diatomaceous rock, heat-treated at 75$0^{\circ}C$ for 30minutes as an optimum pozzolanic form was mixed with OPC(Ordinary Portland Cement) on a weight basis from 0, 2.5, 5.0, 10, 20, 40%. The cement quality was then assessed by the compressive strength and analysis of XRD(S-Ray Diffraction) and SEM(Scanning Electron Microscope).

• Proceedings of the Korean Institute of Building Construction Conference
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• 한국건축시공학회 2022년도 봄 학술논문 발표대회
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• pp.156-157
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• 2022

The purpose of this study is to propose a 40MPa mortar mixed design model that applies the neural network theory to minimize wasted effort in trial and error. A mixed design model was applied to each of the 60 data using fly ash, blast furnace slag fine powder and thickened rice husk powder. And in the neural network model, the optimized connection weight was obtained by repeatedly applying it to the MATLAB. The completed mixed design model was demonstrated by analyzing and comparing the predicted values of the mixed design model with those measured in the actual compressive strength test. As a result of the mixed design verification experiment, the error rates of the double mixed non-cement mortar using blast furnace slag fine powder and rice husk powder at a height of 40MPa were 3.24% and 3.4%. Mixed with fly ash and rice husk powder had an error rate of 3.94% and 5.8%. The error rate of the triple mixed non-cement mortar of the rice husk powder, fly ash, and blast furnace slag fine powder was 2.5% and 5.1%.