• Resources Recycling
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• v.16 no.5
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• pp.13-18
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• 2007

The recycled aggregates produced from waste concrete by crushing and granularity adjusting processes only can't be used for structural aggregates because they display low density and high abrasion rate by including lots of mortar and cement paste. However, the recycled aggregates include a lot of aggregates for concrete. Using the heavy medium separation method that is one of the specific gravity separation methods, about 45% of the waste concrete could be converted to the recycled aggregates.

• Magazine of the Korea Concrete Institute
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• v.9 no.6
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• pp.4-10
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• 1997

• Magazine of the Korea Concrete Institute
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• v.9 no.6
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• pp.11-17
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• 1997

• Magazine of the Korea Concrete Institute
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• v.9 no.6
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• pp.18-22
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• 1997

• Magazine of the Korea Concrete Institute
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• v.9 no.6
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• pp.29-37
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• 1997

• Journal of the Korea Concrete Institute
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• v.13 no.1
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• pp.23-29
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• 2001

This study presented the experimental results on the durability properties of recycled aggregate concrete incorporating fly ash. The main experimental variables were the substitution ratio of recycled aggregate and fly ash, where the substitution ratios of recycled aggregate were 0, 30, and 50%, and those of fly ash were 0, 10, 20, and 30%. The tests for evaluating compressive strength, freezing-thawing resistance, and drying shrinkage were conducted for each specimen. As a result, the compressive strength and the durability of the recycled aggregate concrete were compared from those of ordinary concrete. The followings were conclusion; The compressive strengths of recycled aggregate concrete were less than those of ordinary concrete by 5-10%. However, the durability factor of recycled aggregate concrete remained above 90% at the substitution ratio of 30%. The quality of recycled aggregate concrete were improved by substitution at the range of less that 20% of fly ash and 30% of recycled aggregate.

• Journal of the Korea institute for structural maintenance and inspection
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• v.18 no.3
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• pp.133-142
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• 2014

Recently, more focus is shift to imbalances in aggregate market supply and demand and an exhaustion of natural resources. In this situation, Electric arc furnace oxidizing slag (EAF Slag) has high application possibility as aggregate for concrete due to similar property with general aggregate. In this study, We've got the plan to assure the chemical stability of EAF Slag, and then experimentally tested the mechanical performance and durability for the fine aggregate used EAF Slag. On this test result, we suggest the application plan. At the result of this study, it shows that EAF slag would reduce the surface defect such as pop-out due to natural aging for the fixed hour and adjustment the grain size of EAF Slag. And mechanical performance and durability according to the replacement rate of concrete service, were revealed more than equal or equal compare to general aggregate. Hereafter, quality control must precede not to impede the beauty of concrete surface as assure the safety for aging and processing. And, to establish the environmental resource recycling system for by-products of steel, it should be made development of various application and guideline of quality control for the EAF slag aggregate. Moreover, it must be constantly studied all kind of engineering performance and durability for related to this study.

• Proceedings of the Korea Concrete Institute Conference
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• 2008.11a
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• pp.377-380
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• 2008

Structural lightweight concrete will reduced total loads of supporting sections and foundations in archtectural and civil structures. So, the lightweight concrete can use widely for various purpose in the archtectural and civil structures. However, the performance of lightweight concrete is essentially dependent of properties of used lightweight aggregates. So, in this paper were examined the fresh and hardened properties of lightweight concrete that are used 3types of the differences properties of lightweight aggregates from lower water-ratio to higher water-ratio of concrete mixing regions. Lightweight concrete was somewhat exhibit larger slump loss than ordinary concrete. Also, the development of compressive strength was lower than ordinary concrete, however it was not showed a marked difference. According to types of lightweight aggregates, the case of synthetic lightweight aggregate are highest performance in fresh and hardened concrete, but it is should be to evaluate the structural performance testing as anchoring and bond strength with reinforcing steel bars.

• Journal of the Korean Recycled Construction Resources Institute
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• v.2 no.2
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• pp.145-151
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• 2014

This paper evaluated the quality properties of Finex Water Granulated Slag fine aggregate as part of a study to recycle the Finex Water Granulated Slag generated in korea, and examined the availability as fine aggregate for concrete by comparing properties (properties of fresh concrete, mechanical properties of hardened concrete) of concrete using Finex Water Granulated Slag fine aggregate with properties of concrete using river sand as fine aggregate. From the results of this study, it was found that quality properties of concrete using finex water granulated slag as fine aggregate and concrete using river sand as fine aggregate are equivalent level.

• Journal of the Korean Recycled Construction Resources Institute
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• v.2 no.4
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• pp.321-327
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• 2014

Structural light weight aggregate concrete are made with both coarse and fine light weight aggregates, but it is common with the high strength concrete to replace all or part with normal weight sand be called class 1 structural light weight aggregate concrete. Fire resistance of structural light weight aggregate concrete are determined by properties of high water content ratio and explosive spalling. Especially, structural light weight aggregate concrete is occurred serious fire performance deterioration by explosive spalling stem from thermal stress and water vapor pressure. This study is concerned with experimentally investigating fire resistance of class 1 structural light weight concrete. From the test result, class 1 structural light weight concrete is happened explosive spalling. The decrease of cross section caused by explosive spalling made sharp increasing gradient of inner temperature.