• Magazine of the Korea Concrete Institute
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• v.6 no.4
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• pp.113-122
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• 1994

To examine the applicabilty of the converter furnace slag from iron-works as concrete aggregate respective concrete furnace slag with contents of 20%. 40%, 60%. 80% were mixed with granulated slag, and the strength and stability tests for these specimens were followed. The slump value of the concrete mixed with converter furnace slag was higher than that of the conventional concrete. Furnace slag and granulated slag was increased as the increase of converter furnace content. The strength of the concrete mixed with converter furnace slag and granulate slag increased as an increase of converter furnace content and age. The expansion rate of the concrete mixed with converter furnace slag and granulated slag increased from 0.007% to 0.19% as the converter furnace content changed from 20% to 80%. From the above results in the strength and expansion rate, the concrete with the converter furnace content of 40% was considered to be recommandable for the stable construction of the concrete. Calculated formulas for tensile strength(${\sigma}_t$) and flexural strength(${\sigma}_f$) from the regression a.nalysis of the correlations among these compressive strength (${\sigma}_c$), tensile strength and flexural strength are as follows. ${\sigma}_t$ = 0.16952${\sigma}_c$ - 4.9313 ${\sigma}_f$ = 0.25727${\sigma}_c$ + 6.0528

• Proceedings of the Korea Concrete Institute Conference
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• 1998.04a
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• pp.105-110
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• 1998

The propose of this study is to examine the mechanical properties of mortar using ground granulated blast-furnace(GGBF) slag. In this study, the mortar replaced by varying fineness and content of GGBF slag is investigated through the change of compressive strength, chemical resistance and weight loss. As the result, it has been found that GGBF slag increase somewhat higher flow value and compressive strength. In addition, the chemical resistance of motar using GGBF slag shows higher flow that of motar not containing GGBF slag.

• Journal of the Korean Ceramic Society
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• v.36 no.4
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• pp.410-416
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• 1999

The reactivity of three kinds of spinels which CaO-Al2O3-SiO2 slag was investigated in terms of mineral phases and microstructures. New crystal products were not formed by reaction of 12CaO.7Al2O3 in the slag with spinels and free MgO components was preferenctially dissolved into slag for MgO-rich spinel and stoichiometric spinel. Meanwhile mineral phase was changed from 12CaO.7Al2O3 to CaO.Al2O3 to CaO.2Al2O3 finally to CaO.6Al2O3 having high melting point for Al2O3 -rich spinel. The Fe-oxide component of the slag was taken up by only stoichiometric spinel grains within the spinel clinker and the trapped amount of Fe-oxide was independent of MgO content of MgO in spinel clinker the more th resistance to slag corrosion but the less resistance to slag penetration.

• Resources Recycling
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• v.22 no.6
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• pp.12-18
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• 2013

In this Study, it was fabricated that shrinkage reducing agent and mortar used $C_{12}A_7$-based slag enhanced the shrinkage reduction and compressive strength. To reduce cement content, setting time, flow and compressive strength of mortar with varying content of fly ash and blast furnace slag were experimented. The flow increased and setting time delayed as the increase of fly ash and blast furnace slag content. And early strength was lower and long age strength was higher than that of mortar with low content of admixture.

• Journal of the Korean Ceramic Society
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• v.43 no.7 s.290
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• pp.408-414
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• 2006

Properties of slag cement that contained 50 wt% of blast furnace slag were studied when replaced blast furnace slag powder with electric arc furnace slag powder. Electric arc furnace slag was aged for about 2 months in the air by being crushed to be 1-3 mm in size. As a result of the experiment, it was proven that the water content for obtaining the same consistency became decreased as slag is replaced with electric arc furnace slag instead of blast furnace slag. Also, the workability of mortar increased about 30% at the same ratio of water to binder when blast furnace slag was completely replaced with electric arc furnace slag. The compressive strength of mortar on the 28 days increased when a slag replacement rate became 10 wt%, however, it rather decreased when the slag replacement rate exceeded 10 wt%. The heat of hydration became higher for the first 14 h in case of the replacement of slag cement by electric arc furnace slag. Yet, it decreased when 14 h had passed. Therefore, when all blast furnace slag was replaced with electric arc furnace slag, about 15 cal/g heat of hydration decreased when it passed about 72 h.

• Proceedings of the Korea Concrete Institute Conference
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• 2003.11a
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• pp.318-321
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• 2003

Steel slag is produced during steel making process. Compared with the blast furnace slag, converter slag has the expansibility due to the reaction with water and free CaO. Therefore it is specified in Standard Specification for Concrete in Korea that steel slag aggregate must not be used in concrete. In this study, atomized steel slag aggregate is conducted from converter slag by the atomizing method. Atomized steel slag and conventional converter slag are same in its composite by nature in the converter but compounds of the composite become different because of different method of slag treatment. Especially atomized steel slag aggregate overcomes expansibility that is the weak point for usage. It is researched whether it has the possibility, suitability for fine aggregate in concrete. Slump and air content are measured in fresh concrete, compressive and bending strength in hardened concrete. These is compared with control concrete with washed sand.

• Proceedings of the Korea Concrete Institute Conference
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• 2000.10b
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• pp.911-914
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• 2000

Surface glossing and physical properties of exposed concrete varied with blast furnace slag content are dsicussed in this paper. According to experimental results, as the content of blast furnace slag increases, concrete gains high strength moderately at later stage and surface glossing increase. It shows that glossing decrease with age. Surface glossing shows high as W/B decreases and surface coating is applied. Concrete according to form type shows good results in surface glossing in order for acryl form, fancy form and steel form.

• Resources Recycling
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• v.12 no.5
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• pp.36-41
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• 2003

Although slag has an enough potential as the secondary resources due to its high content of iron, quite a large amount of slags are simply landfilled when market prices of iron and steel are not so beneficial. The purpose of this study is to investigate the basic characteristics regarding the recovery of iron content from slag by magnetic separation method for the enhancement of its recycling rate. Three kinds of slags such as blast furnace slag, water-cooled converter slag, and air-cooled converter slag were tested taking the strength of magnetic field, revolving speed of drum, and feeding rate of slag as the influential factors on the magnetic separation. For blast furnace slag, the recovery of iron was observed to increase as drum speed and feeding rate were lowered. For water-cooled converter slag, iron recovery was raised as feeding rate was increased and drum speed was lowered. Also, finer slag particles were observed to be more favorable for the higher recovery of iron content. Regarding air-cooled converter slags, higher iron recovery was accomplished when both feeding rate and drum speed were increased or decreased. In addition, when the magnetic field strength was increased the iron recovery was raised, however, the iron grade of separated product was observed to diminish because of the co-separation of impurities.

• Proceedings of the Korea Concrete Institute Conference
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• 2001.05a
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• pp.489-494
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• 2001

Several studies have reported that Granulated Blast-Furnace Slag improved the properties of concrete. The Granulated Blast-Furnace Slag could be a good alternative in the shortage of aggregate situation. Slag shows the possibility of influential aggregate and effect of environment preservation. This study presents that the basic properties of fresh concrete using Air-cooled Blast-furnace slag aggregate and Water-cooled Blast-furnace slag aggregate. Testing Factors of this study are concrete slump, slump loss, bleeding, and air contents. The result of this study is below. 1) In case of proportion slag and grave is 50 to 50, the biggest slump value is measured. 2) In the concrete using of air-cooled Blast-furnace slag aggregate, the bleeding capacity is a little. In the concrete using of Water-cooled Blast-furnace slag aggregate, the bleeding capacity goes up to 50% increase. 3) As substitution rate of the granulated blast-furnace slag goes up, air content is increased.

• International Journal of Concrete Structures and Materials
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• v.5 no.2
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• pp.119-123
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• 2011

Presented in the paper are findings of a project that examined the effect of slag grade and cement source on the performance of concrete mixtures. Slag cement contents were 20, 40, and 60 percent of the total cementitious material content. Two grades of slag cement were examined (Gr. 100 and Gr. 120) along with two sources of Type I cement. Compressive strength, durability, and permeability were measured. The results showed that the cement source affected the early age strength of the mixtures. At 28 days of age, mixtures containing Gr. 120 slag cement had higher compressive strengths than mixtures containing Gr. 100 slag cement, but by 90 days of age, the trend reversed. As for the chloride ion penetrability, mixtures cast with Gr. 100 slag cement passed fewer coulombs at 28 and 90 days of age than similar mixtures containing Gr. 120 slag. Mixtures containing Gr. 120 slag had the greatest durability factors.