• 한국세라믹학회지
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• 제49권5호
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• pp.442-447
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• 2012

This study investigated on the early hydration and physical characteristics of BFS by pH variation. NaOH solution was used as a pH activator. In the range from pH 12 to pH 14, Experiment was compared the hydration propertied of OPC(Ordinary Portland Cement) and BFS(Blast Furnace BFS) and BFS containing 2 wt% of gypsum. It was found that CAH(Calcium Aluminate Hydrates) phases and CSH(Calcium Silicate Hydrates) phases were formed during the early hydration of BFS, and that CAH phases, CSH phases and ettringites were formed during the early hydration of BFS containing 2 wt% of gypsum. Furthermore, early hydration of BFS and BFS containing 2 wt% of gypsum were faster then OPC at pH 14, and the 1 day compressive strength of BFS increased by approximately 30% compared to OPC, and BFS containing 2 wt% of gypsum also increased by approximately 40% compared to OPC.

• 한국구조물진단유지관리공학회 논문집
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• 제19권1호
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• pp.90-99
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• 2015

본 연구에서는 최근 콘크리트구조물의 장기내구성을 목적으로 건설 분야에 적극적인 적용이 검토되고 있는 FA 및 BFS를 다량 혼입한 콘크리트의 역학적 및 염분침투성을 실험적으로 검토하여 다음과 같은 결론을 얻었다. FA 및 BFS의 강도시험결과 FA 콘크리트는 FA4000 및 5000을 각각 30% 혼입한 것이 OPC 대비 높은 강도증가율을 나타내는 것으로 파악되었다. 또한, BFS 콘크리트는 BFS8000을 30, 50% 혼입한 콘크리트가 OPC 대비 동등이상의 강도가 확인되었다. FA 및 BFS의 염분침투시험 결과에서는 FA4000 및 5000을 각각 30% 혼입한 콘크리트의 확산계수가 OPC 대비 평균 6.5% 정도 확산계수를 억제할 수 있는 것으로 파악되었다. 또한, BFS 콘크리트의 경우는 BFS6000 및 8000을 각각 50% 혼입한 것이 OPC 대비 각각 253 및 336% 정도 염화물이온의 확산을 효과적으로 억제할 수 있는 것으로 파악되어 BFS의 경우 다량 치환에 따른 염분침투저항성을 극대화시키기 위해서는 50% 정도 혼입하는 것이 가장 유효한 것으로 확인되었다. 한편, FA 및 BFS 콘크리트의 압축강도와 확산계수의 관계에서는 강도가 증가할수록 확산계수는 감소하는 경향이 파악되었다. 본 연구에서는 장기내구성 및 염분침투억제를 목적으로 FA 및 BFS를 콘크리트에 혼입한 결과, FA의 경우는 치환율을 30% 이하로 콘크리트에 혼입하는 것이 가장 유효한 것으로 파악되었다. 한편, BFS의 경우는 분말도가 높을수록 또한, 치환율은 50% 이하의 범위에서 콘크리트에 혼입할 경우 OPC 대비 동등 이상의 강도는 물론 염화물이온의 확산을 보다 효과적으로 억제 할 수 있을 것으로 확인되었다.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2014년도 추계 학술논문 발표대회
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• pp.40-41
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• 2014

As a result of strength test on BFS concrete, those mixed with 30% and 50% of BFS8000, respectively, showed higher or equivalent strength compare to OPC. As a result of test of chloride penetration on BFS, diffusion coefficients of concrete mixed with 30% FA4000 and FA5000, respectively, showed to restrain average 6.5% of diffusion coefficient compared to OPC. And in case of BFS concrete, those mixed with BFS6000 and BFS8000, restrained diffusion of chloride ions 253% and 336%, respectively, compared to OPC. Therefore, Mixing 50% of BFS was most efficient in order to maximize restraint of chloride penetration according to metathesis of large amount. In this study, when mixing BFS to concrete for long-run durability and restraint against chloride penetration, for BFS, as fineness was higher and mixing it to concrete with less or equivalent 50% of replacement rate, there were results of higher strength compared to OPC and more efficient restraint of chloride ions.

• 한국건축시공학회지
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• 제9권6호
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• pp.71-78
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• 2009

하중을 고려한 염분침투성의 평가가 대단히 중요한 것으로 확인되었다. 본 연구에서는 압축응력하에서 Plain콘크리트에서는 47%정도, BFS콘크리트에서는 89%정도 증가 하는 것으로 나타났다. 무하중 상태에서 BFS를 혼입한 콘크리트의 확산계수가 BFS 무혼입 콘크리트에 비해 적은 것이 확인되었다. 이러한 영향은 압축응력이 발생하는 환경하에서도 같은 경향을 나타내었다. 압축응력이 작용하는 환경 하에서 BFS콘크리트는 Plain콘크리트와 같이 하중의 증가와 함께 확산계수가 증가하는 것으로 확인 되었다. 또한, Plain콘크리트에 비해 압축하중의 영향을 크게 받는 것으로 확인 되었다. BFS의 비표면적이 높을수록 확산 계수가 작은 것으로 확인되었고, 이러한 경향은 고응력 환경에서 현저히 나타나는 것이 확인되었다. BFS의 치환율이 증가할수록 확산계수가 작은 것이 확인되었다. 또한, 압축응력이 작용하는 환경 하에서 BFS의 치환에 의한 염분침투성의 억제 효과가 더욱 더 현저히 나타나는 것으로 확인되었다.

• 한국세라믹학회지
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• 제52권6호
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• pp.483-488
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• 2015

Blast furnace slag(BFS) is well known for its hardening mechanism in ordinary Portland cement with alkali activation due to its latent hydraulic property. The possibility of using calcium compound as activator for BFS has been investigated in this study. The hydration properties of calcium compound activated BFS binders were explored using heat of hydration, powder X-ray diffraction and compressive strength testing. Heat of hydration results indicate that the hydration heat of BFS is lower than OPC paste by about 50%. And ettringite as hydration product was formed continuously as the calcium sulfate was decreased. The maximum compressive strength of hardened BFS mortar at 28 days is confirmed to be 83% as compared with hardened OPC mortar.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1999년도 학회창립 10주년 기념 1999년도 가을 학술발표회 논문집
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• pp.297-300
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• 1999

This study was carried out to present the properties of fresh concrete made with ground granulated blast-furnace slag (BFS) powder with variations of blaine and content, and to estimate the utilization of the BFS concrete as admixtural materials for concrete structures of the building. According to the results, the fluidity of concrete which BFS dosage rate was 45% had the considerable difference from that of concrete which BFS dosage rate was not bigger than 35%. Also, the diminution of bleeding was appeared with the increase of blaine and content of BFS. It is concluded that BFS concrete of low blaine can be used effectively in concrete structures of the building.

• 한국세라믹학회지
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• 제44권11호
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• pp.618-621
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• 2007

In this study, flint glass batches with blast furnace slag (BFS) were prepared and the contribution of the BFS to the fining of melts was studied through investigations of the melting and fining characteristics. Additionally, a sulfur redox reaction for BFS-doped melts was examined by square wave voltammetry (SWV). The results of the melting & fining test showed that BFS improved the fining of the melts. In a voltammogram of BFS-doped melts, two reduction peaks were shown at high frequencies while only one peak appeared at low frequencies. The peaks were located at a potential that was similar to those of melts fined by sulfate. From those results it was concluded that sulfide ($S^{2-}$) in BFS has effects in glass melts that are identical to those of sulfate ($SO_4^{2-}$).

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2015년도 추계 학술논문 발표대회
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• pp.53-54
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• 2015

As the result of uniaxial compression strength test on the CLMS mixing BFS and SS with BFS 4000, it required to determine the desired strength through increasing unit quantity of cement in mixing process because of dramatic strength deterioration of strength according to increasing replacing rate. In this study's result, regardless of differences in fine aggregates used, in order to get uniaxial compression strength in the scope exceeding criteria of minimum strength for applying to the field, the most reasonable combination was to mix replacing BFS with fineness of 6000 in 30%. For the CLMS mixing BFS and SS, in order to improve flow ability by securing quantity of minimum unit and to repress bleeding rate with securing uniaxial compress strength considering the field applicability, regardless of differences in fine aggregates used, to mix BFS over 6000 in 30% was most effective.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2000년도 봄 학술발표회 논문집
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• pp.269-274
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• 2000

As a result of the reduction of natural aggregate, most of developed country have been studied the utilization of Blast-furnace Slag(BFS) as aggregate of concrete. bur, in korea there are only basic study about these even though other country are using Blast-furnace Slag production of Ready Mixed Concrete. According, in this study, we carried out fundamental experiments in order to know the material properties of BFS and possibilities of the BFS as fine aggregate of concrete. It is included that analysis concerning material properties of BFS as like specific gravity, absorption. unit weigth, grading including investigation of the surface shape by SEM, also, analysis concerning properties of concrete with BFS as like air-content surface slump. compressive strength .etc.

• 한국세라믹학회지
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• 제45권2호
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• pp.90-93
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• 2008

The oxygen gas behavior in PDP (plasma Display Panel) glass melts doped with sulfate ($SO_4^{-2}$) or blast furnace slag (BFS, $S^{2-}$) or both by means of yttria-stabilized zirconia (YSZ) electrodes was observed after the first fining. The temperature dependence of oxygen equilibrium pressure ($P_{O2}$) in each melt showed typical behavior, namely $P_{O2}$ decreased as temperature decreased. This suggests that an oxidation of $S^{4+}$ to $S^{6+}$ took place. However, the $P_{O2}$-value at constant temperature increased in the following order: BFS$P_{O2}$ of the melt doped with sulfate+BFS was much lower than that of the melt with only sulfate, although only 10% of sulfur was added by the BFS. This behavior can be explained by the redox reaction between sulfide ions in the BFS and dissolved oxygen ions in the melt during the first fining.