• 한국세라믹학회지
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• 제39권1호
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• pp.99-107
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• 2002

임피던스 측정법은 시멘트 페이스트의 수화 진행 시 미세구조의 연속적인 변화를 분석하는데 유용한 수단으로 이용되어 왔다. 본 실험에서는 고로슬래그의 첨가량과 분말도를 달리하여 보통 포틀랜드 시멘트에 첨가한 후 나타나는 페이스트의 초기 수화거동을 임피던스 측정법을 이용하여 관찰하였다. 고로 슬래그가 시멘트에 치환 첨가되면, 수화 초기에는 $R_{t (s+1)}$(고상과 액상에 의한 저항)과 $R_{t(int)}$의 증가폭이 감소하였다. 이것은 고로 슬래그를 포함한 시멘트의 수화가 초기재령에서는 늦게 진행되고 있음을 보여준다. 고로 슬래그의 첨가량이 증가할 수록 $R_{t(s+1)}$이 감소하였으며, 수화 72시간에 출현하는 반원의 직경, $R_{t(int)}$ 역시 고로 슬래그의 첨가량이 증가할 수록 감소하고 있다. 그러나, 첨가된 고로 슬래그의 분말도가 클수록 수화 초기부터 $R_{t(s+1)}$과 $R_{t(int)}$의 수치가 증가하였다.

• Advances in concrete construction
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• 제5권1호
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• pp.65-74
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• 2017

This study was focused on the use of partial replacement of cement with glass powder in high strength concrete and also copper slag as a partial replacement of coarse sand in concrete. The high strength concrete was prepared with different mineral admixtures like silica fume, fly ash and rice ash husk in different proportions. An experimental investigation has been carried to study about the effect of glass powder on high strength copper slag concrete. The range of glass powder was 10%, 15% and 20% as a replacement of cement. The range of copper slag was 0%, 20%, 40% and 60% as a replacement of natural sand. In addition to the different percentage of fly ash, silica fume, and rice husk ash 5% and 10% was also studied in copper slag concrete. Thus, a total of 51 cubes were casted and compressive strength test was performed on them. The result of the study shows that the value of average compressive strength of concrete after addition of 10%, 15% and 20% of glass powder are 70.47, 72.01 and 73.31 respectively. The value of average compressive strength after addition of 20%, 40% and 60% copper slag as a replacement of sand are 72.18, 74.38 and 73.08 respectively. The value of average compressive strength after addition of 5% and 10% fly ash as a replacement of cement are 71.56 and 73.22. The value of average compressive strength after addition of 5% and 10% silica fume as a replacement of cement are 72.33 and 73.53. The value of average compressive strength after addition of 5% and 10% rice husk ash as a replacement of cement are 72.86 and 69.49. At the level of 20% replacement of cement by glass powder meets maximum strength as compared to that of controlled concrete and copper slag high strength concrete.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2020년도 봄 학술논문 발표대회
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• pp.77-78
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• 2020

In Korea, more than 30,000 tons of waste Styrofoam are produced every year. Styrofoam is spent more than 500 years decomposing during the reclamation process, so it needs to be recycled. The recycling rate of waste styrofoam continues to be the third highest in the world, but it is lower than that of Germany and Japan. Therefore, measures are needed to increase the recycling rate of waste Styropol. Another problem is that cement is mainly used in existing lightweight foam concrete. However, large amounts of CO2 from cement-producing processes cause environmental pollution. Currently, Korea is increasing its greenhouse gas reduction targets to cope with energy depletion and climate change, and accelerating efforts to identify and implement reduction measures for each sector. In 2013 alone, about 600 million tons of carbon dioxide was generated in the cement industry. Therefore, this study replaces CO2 generation cement with furnace slag fine powder, uses crude steel cement for initial strength development of bubble concrete, and manufactures hardening materials to study its properties using waste styrofoam. As a result of the experiment, the hardening agent replaced by micro powder of furnace slag was less intense and more prone to absorption than cement using ordinary cement. Further experiments on the segmentation and strength replenishment of furnace slag are believed to contribute to the manufacture of environmentally friendly lightweight foam concrete.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1997년도 봄 학술발표회 논문집
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• pp.163-169
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• 1997

The sea water resistance of cement and concrete must be considered when it is used for construction on the seashore of in the ocean. The concrete specimens using seven type of cements such as ordinary Portland cement, moderate heat Portland cement, sulfate resistance Portland cement, type A. B. C Portland blastfurnace slag cement and Portland flyash cement were immersed for 10 years in seawater in Kunsan. This study proved that moderate heat Portland cement, sulfate resistance Portland cement, type A Portland blastfurnace slag cement had higher resistance for seawater.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2022년도 봄 학술논문 발표대회
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• pp.186-187
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• 2022

The purpose of this study was to give fluidizing properties to non-sirtered cement made using by-products that can replace Portland cement by using a fluidizing agent. Blast furnace slag, C-type fly ash, and F-type fly ash were used for non-sirtered cement, and sand was used for aggregate. The amount of fluidizing agent used was fixed at 1%, and the water-cement ratio (W/C) was different by setting the binder blending ratio of the non-sintered cement differently, and the fluidity test and flow were compared. As a result of the experiment, when the flow standard was 170mm when the fluidizing agent was used, the fluidizing properties were shown at an average water-cement ratio (W/C) of 36%. Through this study, it was confirmed that the fluidizing properties appeared when the fluidizing agent was used in non-sintered cement.

• 한국건설순환자원학회논문집
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• 제6권2호
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• pp.130-137
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• 2018

건설 산업분야에서는 시멘트를 전혀 사용하지 않고 플라이애쉬 또는 고로 슬래그 미분말을 이용한 알칼리 활성화 시멘트에 대한 연구가 활발히 이루어지고 있다. 본 논문에서는 보통 포틀랜드 시멘트 관리에 사용되는 화학적 정량 분석을 알칼리 활성화 슬래그 시멘트의 화학적 정량분석 결과에 적용하여 알칼리활성화 슬래그 시멘트의 역학적 성능에 미치는 영향을 최소화 하고 최적 화학 조성 허용범위를 검토하고자 하였다. 그 결과 수경율 및 석회포화도의 비율 및 계수는 모두 일정한 범위 내에 있음이 확인되었다.

• 한국세라믹학회지
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• 제39권12호
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• pp.1138-1142
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• 2002

유해 중금속을 함유하고 있는 제철 폐기물 슬러지를 안전하게 처리하기 위하여 고로 수쇄 슬래그와 포틀랜드 시멘트를 이용한 중금속 고화용 슬래그 시멘트, 고황산염 시멘트를 제조하여 폐슬러지의 고화를 시도하였다. 고로 수쇄 슬래그와 보통포틀랜드 시멘트를 6:4로 혼합하고 여기에 자극제로서 CaO를 10% 가한 슬래그 시멘트 재료를 사용한 경우, STS 슬러지는 C-S-H 그리고 ettringite와 monosulfate 등의 수화물이 생성되면서 강도가 지속적으로 증가함을 보여주고 있지만 성상과 성분이 다른 BF 슬러지와 COREX 슬러지에 적용하였을 때는 강도 발현이 좋지 않았다. 하지만 고화처리용 슬래그 시멘트를 이용하여 STS에 BF 및 COREX 슬러지를 각각 5:5로 혼합한 혼합슬러지에 적용한 경우 고화체의 강도는 슬래그 시멘트를 이용한 경우 폐기물 고화 처리 기준을 상회하는 충분한 강도를 보였다. 한편, 수쇄슬래그, 반수석고, 보통 포틀랜드 시멘트에 자극제를 혼합한 폐기물 처리용 고황산염계 시멘트를 이용하여 고화가 힘들었던 COREX 슬러지에 적용한 결과, 3일 강도가 이미 고화처리기준을 상회하는 좋은 결과를 얻어, 이 시멘트 재료로서 COREX 슬러지의 고정/안정화도 가능함을 보여주고 있다.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2023년도 가을학술발표대회논문집
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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.

• Structural Engineering and Mechanics
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• 제82권2호
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• pp.133-149
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• 2022

This study investigates the resistance of sustainable ultra-high performance concrete (UHPC) on steel reinforcement corrosion. For enhancing the sustainability of UHPC, concrete mixes were prepared with ordinary Portland cement main binder, and mixes with moderate to high percentages of blast furnace cement (CEM III), fly ash (FA), and slag cement as partial replacements of the full quantity of the used cement. Linear polarization resistance technique was employed to estimate the electrochemical behavior of the concrete specimens. Results showed that the compressive strength and the resistance of steel to corrosion in marine environments can be enhanced by improving the sustainability of UHPC through incorporation of CEM III, FA, and slag cement. FA replacement of up to 50% with the addition of 15% SF content produced better compressive strength and steel corrosion resistance than slag cement whether with the use of ordinary Portland cement or blast furnace cement as the main binder.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2002년도 가을 학술발표회 논문집
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• pp.579-584
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• 2002

In this research, the physical properties of self compacting concrete using ground granulated blast furnace slag as a part of cement were investigated. Concrete using ground granulated blast furnace slag was prepared with various ground granulated blast furnace slag replacement(20~80 volume %) for cement and the quantities of coarse aggregate in concrete were 50%, 55% and 60% of ratio of absolute volume of coarse aggregate. The workability, flowing characteristics, air content and compressive strength of concrete using ground granulated blast furnace slag were tested and the results were compared with those of ordinary portland cement concrete. In the experiment, we acquired satisfactory results at the point of flowing characteristics and strengths of concrete using ground granulated blast furnace slag within tile replacement ratio of 50% and the optimum quantity of coarse aggregate in concrete was found to be 50%~55% of ratio of absolute volume of coarse aggregate.