• Journal of the Korea Concrete Institute
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• v.14 no.3
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• pp.315-320
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• 2002

The effects of slag content and polymer-binder ratio on the strength properties of the polymer-modified concretes using ground granulated blast-furnace slag and a styrene-butadiene rubber (SBR) latex are examined. As a result, the compressive, tensile and flexural strengths of the SBR-modified concretes using slag increase with increasing polymer-binder ratio and slag content, and maximized at a slag content of 40 ％. In particular, the SBR-modified concretes with a slag content of 40 ％ provide approximately two times higher tensile and flexural strengths than unmodified concretes. Such high strength development is attributed to the high tensile strength of SBR polymer and the improved bond between cement hydrates and aggregates because of the addition of SBR latex.

• Journal of the Korean Recycled Construction Resources Institute
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• v.8 no.1
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• pp.18-24
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• 2013

Recently, the interest is increasing about the eco-friendly concrete. Accordingly, the blast furnace slag(BFS), a by-product of industry is known for improving the durability through compaction in concrete and is expanding the use. The research about BFS in concrete be accomplished frequently. In this study, we should know the hydration characteristic of BFS concrete the through the adiabatic temperature rise test due to the replacement of a variety of BFS. In addition, we produced the regression analysis factors through the test result and analyzied the effect for the replacement of BFS. According to test results, the compressive strength showed a slight degradation or equal and the the adiabatic temperature rise figure and rising factors are went down for rising replacment of BFS. In the future, the study about the adiabatic temperature rise equation for the various replacement of BFS and binder is considered necessary.

• Magazine of the Korea Concrete Institute
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• v.9 no.5
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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.

• Journal of the Korea Concrete Institute
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• v.14 no.4
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• pp.608-614
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• 2002

The effects of slag content and polymer-binder ratio on the strength properties of autoclaved SBR-modified concretes using ground granulated blast-furnace slag(slag) and a styrene-butadiene rubber (SBR) latex are examined. As a result, the compressive and tensile strengths of the autoclaved SBR-modified concretes using slag increase with increasing slag content, and reach a maximum at a slag content 40％, and increase with increasing polymer-binder ratio. In particular, the autoclaved SBR-modified concretes with a slag content of 40％ provide about three times higher tensile strength than unmodified concretes. Such high strength development is attributed to the high tensile strength of SBR polymer and the improved bond between cement hydrates and aggregates because of the addition of SBR latex.

• Journal of the Korean Recycled Construction Resources Institute
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• v.5 no.1
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• pp.45-52
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• 2017

This study evaluated the durability of nuclear power plant concrete. The main parameters were the water-to-binder ratio and admixture type. The results revealed that high-volume ground granulated blast-furnace slag(GGBS) concrete had lower initial strength, while the strength reached higher after 28 days. On the other hand, the initial strength of fly ash blended concrete was high, but the long-term strength of the robbery was low. The measured durability of GGBS blended concrete was found to be better than that of the existing concrete mix for use in the construction of nuclear power plants. Especially, the GGBS blended concrete was more durable than the fly ash blended concrete in terms of chloride attack, carbonation resistivity and freezing-thawing durability in low compressive strength. The effects of concrete compressive strength according to gamma rays were minor.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.10
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• pp.271-279
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• 2016

This study examines the properties of high-fluidity concrete after adding copper slag as a mineral admixture. For this purpose, the replacement ratio of cement to copper slag was varied to 0, 10, 20, 30, 40, and 50%. A slump flow test, reach time slump flow of 500 mm, and a U-Box and O-lot test were conducted on the fresh concrete. The compressive strength of the hardened concrete was determined at 3, 7, 14 and 28 days. According to the test results, the workability, compaction, and compressive strength of the high-fluidity concrete increased when replacing 30% of the cement with copper slag. These parameters decreased for all material ages with more than 30% copper slag, which was the optimal mixture ratio.

• Journal of the Korea Concrete Institute
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• v.14 no.1
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• pp.92-99
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• 2002

This paper is Intended to investigate physical properties and surface glossing of exposed concrete incorporating granulated blast furnace slag(BS). According to test results there is no remarkable variations in fluidity and air content with increase of BS, but unit weight shows decline tendency Compressive strength at later age gains considerably due to potential hydraulicity reaction of BS. It shows that drying shrinkage increases. It is found that low W/B, surface coating and high BS content lead to favorable effects on the surface glossing of exposed concrete because of filling effects on the voids of the concrete. It is improved by about 7 ％ with increase every 10 ％ of BS content. The effects of form pannel kinds on the improvement of surface glossing are in order for acryl, fancy, steel and wood.

• Proceedings of the Korea Concrete Institute Conference
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• 2008.04a
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• pp.669-672
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• 2008

To analyze possibility for high performance concrete that massively displaces blast furnace slag, this study analyzed the characteristics of concrete by blast furnace slag displacement rate changes, and the results are summarized as follows. Firstly, as for fresh concrete characteristics, flow tended to increase and air amount decreased with increase in blast furnace slag displacement rate, and settling time was shown delayed. As for hardened concrete characteristics, in conditions where blast furnace slag displacement rate increased up to 50%, the compressive strength decreased below OPC at early age, however at age 28 days, its level was no less than that of OPC, and as for temperature rise by simple insulation, it decreased as displacement rate increased at early stage of hydration, but in the latter stage, hydration progress slowed down and hydration heat increased.

• Journal of the Korea Concrete Institute
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• v.29 no.3
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• pp.299-306
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• 2017

In this research, it was examined chloride ion penetration resistance of slag-replaced concrete and cementless slag concrete considering marine environmental exposure conditions of splash zone, tidal zone and immersion zone. In the design strength of grade 24 MPa, the specimens were tested to determine their compressive strength, scanning electron microscopy images and chloride migration coefficient. Further, chloride ion penetration depth and carbonation depth of specimens exposed to marine environment were measured. Experimental results confirm that chloride migration coefficient of specimens tended to decrease with increasing the replacement ratio of ground granulated blast-furnace slag in accelerated laboratory test. In addition, the specimens exposed to the tidal zone were found to be the greatest chloride ion penetration depth compared to splash zone and immersion zone. On the other hand, the chloride ion penetration depth of the specimens exposed to splash zone tended to increase with increasing the replacement ratio of ground granulated blast-furnace slag in contrast with the results for the tidal zone and immersion zone.

• Journal of the Korea institute for structural maintenance and inspection
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• v.21 no.3
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• pp.54-59
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• 2017

GGBFS (Ground Granulated Blast Furnace Slag) is a byproduct with engineering advantages and HVSC (High Volume Slag Concrete) is widely attempted due to active utilization and reduction of eco-load. In the present work, characteristics of drying shrinkage and early-aged behavior are evaluated for the concrete with 65% replacement ratio of GGBFS and 50MPa of design strength. For the work, 3 different mix conditions are considered and several tests including slump flow, compressive strength, drying and autogeneous shrinkage are performed. From the test, OPC 100 mixture without replacement shows higher strength development before 7 days, however the strength reduction in concrete replaced with GGBFS is not significant due to sufficient free water for cement hydration. OPC 100 mixture also shows significant drying shrinkage due to a great autogeneous shrinkage before 3 days. In the concrete with GGBFS replacement, the drying shrinkage behavior is improved due to relatively small deformation by autogeneous shrinkage. The mixture (OPT BS 65) with lower w/b ratio (0.27) and unit content of water ($160kg/m^3$) shows more improved shrinkage behavior than BS 65 mixture which has simple replacement of GGBFS with 0.30 of w/b and $165kg/m^3$ of water unit content.