• 한국건축시공학회지
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• 제11권4호
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• pp.345-352
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• 2011

연구의 목적은 반응성 골재를 함유한 알칼리 활성화 고로슬래그 미분말의 알칼리-골재반응으로 인한 팽창을 조사하기 위한 것이다. 또한 이 연구는 현재 존재하고 있는 반응성 골재와 알칼리 재료들의 거동과 관련하여 특별히 관여 되어 지고 있다. 실험 방법은 EDS, SEM을 통하여 알칼리-실리카 반응 생성물의 구성이나 미세구조를 관찰하였으며 알칼리-실리카 반응에 의한 모르터 바의 팽창정도를 측정하였다. 실험 결과에 따르면 알칼리-활성화된 모르터는 알칼리 실리카 반응 때문에 팽창이 되었지만 14일 재령에서 0.1%의 팽창률을 나타내어 알칼리-실리카반응에 대하여 안전한 것으로 나타났다. 그리고 촉진 실험 후 SEM과 BEM분석한 결과 골재 주변과 시멘트 페이스트에 알칼리-실리카 겔 및 띠 모양의 생성물이 나타난 것을 볼 수 있었다. EDX에 따르면 반응생성물이 알칼리 활성화 고로슬래그를 사용하였을 경우 현격히 감소한 것을 볼 수 있다. 추가적으로 광물학적 혼화재료의 대체 재료로써 콘크리트 내구성의 특성을 보증하기 위하여 알칼리 활성화 고로슬래그의 품질을 향상시키는 연구가 필요하다.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2012년도 추계 학술논문 발표대회
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• pp.81-82
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• 2012

The purpose of this study is the hydration properties of motar using Blast-Furnace Slag(BFS) with water elured from recycled coarse aggregate. The results of the experiment show that the water eluted from recycled coarse aggregate mixed with blast furnace slag has comparatively higher hydration activity than the mortar not mixed with one in early-age mortar causing the calcium hydroxide in the recycled coarse aggregate to work on as a stimulus to the hydration of ground granulated blast furnace slag. BFS mixed with the eluting water the hydration reaction was a promotion.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1999년도 봄 학술발표회 논문집(I)
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• pp.625-630
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• 1999

This study was carried out to investigate quantitatively the relatonship between the water binder ratio and the concrete strength using finely ground granulated furnace blast slag to apply f 0.5% type admixture. The experimental parameters are water-binder ratio (40, 45, 50, 55, 60%) and slag contents(0, 10, 20, 30%). As a result, it can make that the water-binder ratio of concrete contented slag can be calculated by equation using relationship between compressive strength of concrete and water-binder ratio which is consisted of mixing strength and cement strength K.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2001년도 The 6th International Symposium of East Asian Resources Recycling Technology
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• pp.508-513
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• 2001

Recently, ground granulated blast-furnace slag (GGBFS) has been increasingly used as additive for concrete. Many researchers reported that concrete using GGBFS had a better resistance under severe environments, such as marine or sulfate-rich soils, than Portland type cement concrete. The aim, therefore, of this study is to evaluate on the effectiveness of concrete using GGBFS when the concrete exposes to sulfate-rich environment. The detailed items for experiments show 2 series consisted of sulfate immersion test with mortar and sulfate diffusion test with concrete. The sulfate immersion test was performed for 400 days and contained reduction of compressive strength, length change and XRD analysis. For sulfate diffusion test, sulfate ions diffusivity was calculated on tile consideration of electrochemical theory by the diffusion cell test. As the results of this study, it was found that the concrete using GGBFS as additive was superior to portland type cement concrete. Consequently, the use of concrete with GGBFS for recycling may expect the durable and economical benefits.

• 한국건설순환자원학회논문집
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• 제6권3호
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• pp.69-78
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• 2011

최근 콘크리트제품에 대한 고급화, 고품질화 및 고강도화 등의 추구로 변화함에 따라 구조물의 미적효과와 전시 목적의 제품 고급화를 위해 반투명 콘크리트를 제작하였다. 본 연구에서는 반투명 콘크리트의 제조기법 개발을 통해 다양한 형상의 블록 제조방식을 소개하고, 또한 반투명 콘크리트의 물성 평가와 더불어 경제적인 반투명 콘크리트 제조를 위해 무기혼화재인 고로슬래그와 플라이애시의 활용 및 유리알갱이의 적용방안에 대해 검토하였다. 물성평가 결과, 반투명 콘크리트 블록의 28일 압축강도는 32.2MPa이고 탄성계수와 푸아송비는 일반 콘크리트 블록에 비해 증가되어 압축을 받는 부재일 경우 일반 콘크리트 구조물과 같이 구조적 용도로도 사용이 가능하다는 것을 알 수 있었다. 시멘트 대체재로써 플라이애시 적용하였을 때 동일 양의 광섬유를 포함한 반투명 콘크리트 블록의 28일 강도의 85~96%의 값을 보였으며, 고로슬래그 미분말을 적용하였을 때에는 82~96%의 값을 보였다. 또한, 광섬유대체재로서 유리알갱이를 적용한 결과, 빛의 투과효과가 전혀 나타나지 않아 대체효과가 전혀 없는 것으로 나타났다.

• Advances in concrete construction
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• 제6권2호
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• pp.103-121
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• 2018

This paper reports the effects of coarse and fine recycled concrete aggregates (RCA) on fresh and hardened properties of self-compacting concrete (SCC) containing ground granulated blast-furnace slag (GGBFS) as cement replacement. For this purpose, three SCC mixes groups, were produced at a constant water to binder ratio of 0.38. Both fine and coarse recycled aggregates were used as natural aggregates (NA) replacement at different substitution levels of 0%, 25%, 50%, 75% and 100% by volume for each mix group. Each group, included 0, 15% or 30% GGBFS as Portland cement replacement by weight. The SCC properties investigated were self-compactability parameters (i.e., slump flow, T500 time, V-funnel flow time, L-box passing ability and sieve stability), compressive strength, capillary water absorption and water penetration depth. The results show that the combined use of RCA with GGBFS had a significant effect on fresh and hardened SCC mixes. The addition of both fine and coarse recycled aggregates as a substitution up to 50% of natural aggregates enhance the workability of SCC mixes, whereas the addition from 50 to 100% decreases the workability, whatever the slag content used as cement replacement. An enhancement of workability of SCC mixes with recycled aggregates was noticed as increasing GGBFS from 0 to 30%. RCA content of 25% to 50% as NA replacement and cement replacement of 15% GGBFS seems to be the optimum level to produce satisfactory SCC without any bleeding or segregation. Furthermore, the addition of slag to recycled concrete aggregates of SCC mixes reduces strength losses at the long term (56 and 90 days). However, a decrease in the capillary water absorption and water permeability depth was noticed, when using RCA mixes with slag.

• 콘크리트학회지
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• 제9권5호
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• pp.149-155
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• 1997

고로슬래그 미분말을 사용한 콘크리트\ulcorner 수화속도가 느려 어린 재령시 동해의 영향을받기 쉽다. 본 연구에서는 고로슬래그 미분말을 사용한 콘크리트의 동결융해 저항성을 알아보기 위해 고로슬래그 미분말의 치환율과 물-결합재비를 변화시켜 제조한 콘크리트에 대해 동결융해시험을 실시하였다. 또한 동일한 치환율, 물-결합재비의 콘크리트에 AE제를 첨가시켜 동결융해 저항성의 개선효과를 알아보았다. 시험결과 고로슬래그 미분말의 치환율이 증가할수록 동결융해 저항성은 작게 나왔다. 또한 non-AE 콘크리트의 경우 물-결합재비가 51%, 45%일 때 내구성지수는 각각 2.4%, 40.0%이하로 매우 나쁘게 나타났으나, AE콘크리트의 경우 물 -결합재비가 45%와 51%인 콘크리트의 내구성지수는 각각 90.2% 80.9%이상으로 동결융해 저항성이 매우 우수하게 나타났다.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1999년도 학회창립 10주년 기념 1999년도 가을 학술발표회 논문집
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• pp.107-110
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• 1999

The objective of this study is to obtain characteristics of early age pore-structure and carbonation of concrete using ground granulated blast furnace slag (GGBFS). The durability of GGBFS concrete should be evaluated for wide use of the GGBFS. As for that evaluation, an analysis on early age pore-structure characteristics of GGBFS concrete are very important, Carbonation depths of GGBFS concrete, which are known to be larger than that of OPC, are different according to replacement ratios and fineness of slag. Because sea sand as fine aggregate is much used recently, it is also necessary to analyze characteristics of carbonation of GGBFS concrete. In this study, The micro-pore structure formation characteristics of GGBFS concrete are obtained through the test of GGBFS mortars with different fineness and replacement ratio of GGBFS. The carbonation of GGBFS concrete is also investigated by acclerated carbonation test for early age GGBFS concrete.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2001년도 봄 학술발표회 논문집
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• pp.313-318
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• 2001

The cost of producing ready mixed concrete(remicon) has increased due to the rising cost of raw materials for concrete and transportation caused by the upturn of oil price. In contrast, its orders have also decreased due to the recession of the construction industry. In addition, the cost of delivery has decreased owing to the excessive competition among manufacturing companies, so manufacturing companies began mixing ground granulated blast-furnace slag or fly ash to lower the cost. However, there is no way to determine whether the strength of the concrete using the admixture is satisfied or dissatisfied with design strength at the early age. The purpose of this study is dedicated to early strength estimation of concrete mixed with an admixture, ground granulated blast-furnace slag.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2000년도 가을 학술발표회논문집(I)
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• pp.425-428
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• 2000

When concrete structures are exposed to sulfate or marin environments, sulfate ions penetrated into concrete make it deteriorate. An accelerated test under potential difference method was performed to evaluate not only the sulfate ion diffusivity in ordinary portland cement and ground granulated blast-furnace slag cement concretes but the effect of slag replacement and water-cement ratio on the sulfate ions diffusivity. As the result of this study, we assumed the sulfate ion diffusivity was significantly related with total passed charge and initial current in concrete. Moreover sulfate ions penetration resistance of ordinary portland cement concrete was superior to that of ground granulated blast-furnace slag cement concrete.