• Computers and Concrete
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• v.7 no.1
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• pp.17-38
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• 2010

This research aimed to investigate the influence of high-volume mineral admixtures (MAs), i.e., fly ash and slag, on the hydration characteristics and microstructures of cement pastes. Degree of cement hydration was quantified by the loss-on-ignition technique and degree of pozzolanic reaction was determined by a selective dissolution method. The influence of MAs on the pore structure of paste was measured by mercury intrusion porosimetry. The results showed that the hydration properties of the blended pastes were a function of water to binder ratio, cement replacement level by MAs, and curing age. Pastes containing fly ash exhibited strongly reduced early strength, especially for mix with 45% fly ash. Moreover, at a similar cement replacement level, slag incorporated cement paste showed higher degrees of cement hydration and pozzolanic reaction than that of fly ash incorporated cement paste. Thus, the present study demonstrates that high substitution rates of slag for cement result in better effects on the short- and long-term hydration properties of cement pastes.

• Proceedings of the Korea Concrete Institute Conference
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• 2003.05a
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• pp.89-94
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• 2003

In this research, the physical properties of self compacting concrete using ground granulated blast furnace slag and fly ash as a part of cement were investigated. Concrete using ground granulated blast furnace slag and fly ash was prepared with various ground granulated blast furnace slag(30-50 volume %) and fly ash(10-20 volume %) replacement for cement. The effect of each of the materals, which have effects on self compacting concrete made by the basic mix proportion used granulated blast furnace slag and fly ash after hardening, has been checked. The workability, flowing characteristics, resistance of segregation of materals, air content, and compressive strength of concrete using ground granulated blast furnace slag and fly ash 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 and slag fly ash within the replacement ratio of 65%

• Proceedings of the Korean Institute of Building Construction Conference
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• 2016.10a
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• pp.117-118
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• 2016

This paper evalutes properties of extruding cement panel using Ca-extracted convert slag and air-cooled blast furnace slag. Flexural strength of extruding cement panel has measured in air dry and autoclave curing as basic study for use as silicious source. As a result, when Ca-extracted converter slag replaces 25% in autoclave curing, flexural strength measures 13.1MPa better than panel control mix. In result of using air-cooled blast furnace slag, Ca-extracted air-cooled blast furnace slag dose not show increase of flexural strength.

• Journal of the Korean Ceramic Society
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• v.22 no.2
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• pp.33-38
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• 1985

The hydration of supersulphated slag cement which is the mixture of granuloated blast furnace slag anhydrite $C_4A_3$ type clinker and calcined dolomite was studied by X-ray diffraction differential thermal analysis scanning electron microscope observation and measurement of the rate of heat liberation. The main hydrates were ettrigite and C-S-H. This supersulphated slag cement enhanced rapid-hardening and increased in strength at early stage due to the much of ettrigite. Furthermore the hardened cement became stronger due to the C-S-H that was produced from the hydration of the $eta$-$C_2S$ in $C_4A_3$ type clinker and the hydration of the dissolved components from slag at later period.

• Proceedings of the Korean Geotechical Society Conference
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• 2010.09a
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• pp.998-1001
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• 2010

Most firming agent used in Korea is cement-firming agent. Cement-firming agent absorb water for combination, and then it makes ettringite. Through this chemical process, soft ground is firmed by cement-firming agent. Although most cement-firming agent used in Korea made from CSA, it relies on imports. Therefore, the development of soft ground firming agent using new materials is required. In this study, we suggested that EAF reduction slag not used for anything in the steel industry is available for material of soft ground firming agent. If EAF reduction slag is used in soft ground firming agent, it will be possible to solve the problem with treatment of slag and improvement of soft ground.

• Journal of the Korean Ceramic Society
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• v.36 no.7
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• pp.685-690
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• 1999

Modified belite cement clinker containing $\alpha$'-C2S and C4A3 were syntehsized form the mixture of raw materials. $\alpha$'-C2S was stabilized at room temperature by adding borax. Properties of the clinker were charaterized with a XRD, SEM, TEM The additive effects of slag on the hydration properties were also estimated by measurement of compressive strength fluidity and heat evolution. The experimental results exhibited that the addition of slag to the belite cement improves the fluidity and early compressive strength due to the formation of ettringite and C-S-H. The compressive strengths of the mortar with 20% slag after 7, 90 days hydration were 212, 355 kgf/cm2 respectively.

• Proceedings of the Korea Concrete Institute Conference
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• 1997.10a
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• pp.203-206
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• 1997

In this paper, the properties of Interlocking block contained blast furnace slag cement are compared with that with O.P.C.(ordinary portland cement) and are analyzed under various mix proportions and the dosage of AE agent. According to the experimental results, compressive strength and flexural strength of interlocking block with blast furnace slag cement are lower than that with OPC. Also the strength and the ratio of absorption decrease with higher dosage of AE agent. although interlocking block with OPC has better performance than that of blast furnace slag in the side of quality, it is worth while to use the blast furnace slag as materials of interlocking block considered the side of recycling of resources and economy.

• Magazine of the Korean Society of Agricultural Engineers
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• v.40 no.5
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• pp.59-67
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• 1998

The object of this study is to investigate the strength characteristics and the freeze-thaw resistance of high strength concrete incorporating fine blast furnace slag. Major experimental variables were the water/cement ratio, maximum size of coarse aggregate, and cement types such as ordinary portland and slag cement. The results were as follows ; The workability of fresh concrete incorporating fine blast furnace slag was better than that of OPC(ordinary Portland cement) in terms of slump. The freeze-thaw resistance showed better than that of OPC, keeping more than 90% of relative modules of elasticity after 506 cycles and showing only a hair crack at surface without serious damage. Thus, the fine blast furnace slag might be recycled at concrete to make high strength concrete at fields.

• Journal of the Korean Ceramic Society
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• v.35 no.4
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• pp.339-346
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• 1998

Active belite cement clinkers were synthsized by using natural raw materials with borax and calcium phosphate ({{{{ {Ca }_{3 }( {PO}_{4}) }}2) In both case {{{{alpha ^、 {C }_{2 }S }} were formed but borax was more efficient. The cement syn-thesized with the addition of borax was hydrated with the addition of anhydrite(5 wt%) and slag(30wt%, 40wt% 50wt%) The addition of 50wt% slag with anhydrite was good for strength development in 7days and the compressive strength was developed to twice than no addition of slag at 28 days strength.

• Proceedings of the Korea Concrete Institute Conference
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• 2000.04a
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• pp.231-236
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• 2000

In this study, to present the use of the blase furnace slag fly ash derived from a large amount of the industrial products with the early strength reduction of it prevented, the initial strength is measured after a large quantity of fly ash and the required stimulus agent for the high development of the initial strength was added in blast furnace slag cement. As the results, in spite of the much addition of fly ash in blast furnace slag, the long-age strength of blast furnace slag cement was able to be improved by a proper amount of stimulus agent, and was as high as that of ordinary portland cement.