• Journal of the Korean Ceramic Society
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• v.41 no.2
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• pp.176-181
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• 2004

EAF (Electric Arc Furnace) dust is classified as special wastes containing heavy metal contaminants may cause to damage an environment such as underground water contamination if they were not treated properly. For reutilizing the EAF dust, the porous body was made from EAF dust/clay composition system, and analyzed pore characteristics. It was found that a light-aggregate body was made up two different microstructures. One was non-black and dense microstructure which located near surface, and the other was black and porous microstructure (black coring) which located inner part. For systematizing the relationship of the black-coring area and the bloating degree, we defined the Ic(core index) and Is(shell index). It was found that the optimal bloating conditions of artificial light-weight aggregate were more than 0.5 of Ic and 0.4 of Is.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2003.05a
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• pp.35-38
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• 2003

The purpose of this study is to investigate the manufacture of light weight concrete panel using the artificial light-weight aggregate as a part of the substitution of foamed styrene and polyurethane because of narrow allocable temperature Bone in use. The experimental parameter of this study is 40, 60 and 8$0^{\circ}C$ of curing temperature at 100% relative humidity and the type of admixture such as cement, 6mm glass fiber and St/BA emulsion. Testing item is compressive and flexural strength and strength of specimen cured at standard condition is compared to that of specimen cured at 40, 60 and 8$0^{\circ}C$ of curing temperature at 100% relative humidity. As a result or this, it was revealed that the maximum or strength is developed in 6$0^{\circ}C$ or cure temperature at 100% relative humidity in case of the most of the specimen. Specimens modified by St/BA emulsion show the highest development of strength dependent on the curing tmeperature. So, it seems to be effective that evaporation curing method shoud be considered to curing the specimen as the panel core.

• Journal of Powder Materials
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• v.13 no.2 s.55
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• pp.102-107
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• 2006

Recycling industrial wastes such as fly ash from a coal burning heat power plant and shell from an oyster farming were investigated to prevent environment contamination as well as to enhance the value of recycling materials. In this study, the lightweight aggregates and the red bricks were fabricated from fly ashes with other inorganic materials and wastes. The starting materials of the lightweight aggregate were fly ash powder and water glass, and the compacts of these materials were heat treated at $1100^{\circ}C$. The fabricated lightweight aggregates had low bulk density, $0.9-1.2\;g/cm^3$, hence floated on the water and had the strength of 7.0-11.0 MPa and the modulus of 2900-3300 MPa which indicates it has enough strength as the aggregate. Another type of the light weight aggregate was prepared from fly ashes, shell powders and clays. The bulk density, porosity, and compressive strength of these aggregates were $1.19-1.34\;g/cm^3,\;18.3{\sim}56.1%$ and 5-12 MPa, respectively. The addition of a small amount of fly ash powder prevented hydration of the light weight aggregates. The red brick was also fabricated from the fly ash containing materials. It is suitable for the brick facing of a building as it has moderate strength and low water absorption rate.

• Proceedings of the Korea Concrete Institute Conference
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• 2003.05a
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• pp.31-34
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• 2003

This study performed to develope the concrete using artificial lightweight aggregate(LWA) which contains stabilized heavy metal from EAF -dust. L W A is very effective to stabilize the heavy metal EAF-dust satisfied the general physical properties of aggregate except a absorptivity. The thermal conductivity and the dry shrinkage of LWAC were excellent compared with plain concrete and the strength was little fallen to.

• Proceedings of the Korea Concrete Institute Conference
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• 1999.04a
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• pp.187-190
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• 1999

This study is intended to present the properites of planting concrete using the light-weight aggregate and crushed aggregate. According to the result of experiment, the concrete using orchid stone shows a better performance in voids volume, unit weight, absorbtion, thermal conductivity and pH, which are helpful for planting and heat isolation. Therefore, if planting concrete used with orchid stone are utilized to be the planting base on the building's roof, it will be effective to reduced the cost of construction and heating due to the redution of building's self weight and heat isolation effection.

• Resources Recycling
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• v.16 no.4
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• pp.61-67
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• 2007

In viewpoints of environmental and resource conservation, it is desirable to utilize fly ash generated from domestic coal power stations as light constructive material. Furthermore, the demand of light constructive materials has been increased as many building tend to become highly multistory buildings. In demonstration of converting fly ash to light constructive materials, the Dwight-Lloyd kiln of which the operation is relatively easy and the reliability very high has been informed to be only commercialized plant over the world. In this review, Dwight-Lloyd kiln plant operated at Oomura coal power station in Japan is explained. Circular grate kiln, Shaft kiln, Rotary kiln plants that are under developed is also introduced.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2011.11a
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• pp.175-176
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• 2011

Applying previous studies performed in the moisture transportation characteristics and shrinkage of lightweight concrete application of shrinkage reduction is to discuss. Applicability of shrinkage reduction effect of lightweight concrete applies for the analysis of PSC girder bridge beam placed on the construction site. Stress of the concrete bridge deck, rebar quantity is calculated by effective elastic modulus method and crack risk is assessed by moisture transport and differential shrinkage analysis. After approximately 10 days maximum tensile stress occurs 6MPa, similar to the case of normal concrete, a maximum tensile stress occurs 3MPa in lightweight concrete and comparing to normal concrete stress was reduced to approximately 50%. Normal and lightweight concrete crack index, respectively, is reduced 1.6 to 1.2, 1.2 to 0.9 in surface and boundary region. Therefore, reduction in shrinkage of concrete were able to confirm reduction of crack risk.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2016.05a
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• pp.221-222
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• 2016

The replacement ratio of waste EPS was varied, and its effect on compressive strength and absorption capacity was investigated. According to the experimental results, The 28th day compressive strengths for the W/C 50% specimens were 17.5~21.2MPa, which was relatively low compared to the 13.6~22.2MPa of the W/C 70%.

• Journal of the Korean Ceramic Society
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• v.41 no.3
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• pp.221-228
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• 2004

Basic properties of artificial lightweight aggregate by using waste dusts and strength properties of LWA concrete were studied. Bulk specific gravity and water absorption of artificial lightweight aggregates varied from 1.4 to 1.7 and 13 to 16%, respectively. Crushing ratio of artificial lightweight aggregate was above 10% higher than that of crushed stone or gravel. As a result of TCLP leaching test, the leaching amount of tested heavy metal element was below the leaching standard of hazardous material. Slump, compressive strength and stress-strain properties of LWA concrete made of artificial lightweight aggregate were tested. Concrete samples derived from LWA substitution ratio of 30 vol% and W/C ratio of 45 wt% showed the best properties overall. Thermal insulation and sound insulation characteristics of light weight concrete panel with the optimum concrete proportion were tested. Average overall heat transmission of 3.293W/㎡$^{\circ}C$ was observed. It was higher by about 15% than those of normal concrete made by crushed stone. Sound transmission loss of 50.9 ㏈ in frequency of 500 ㎐ was observed. It was higher by about 13% than standard transmission loss.

• Proceedings of the Korea Concrete Institute Conference
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• 2010.05a
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• pp.229-230
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• 2010

By using the experiment, it can analyze strain properties of that when the concrete using light and nomal-weight aggregate takes a various under-loading level at elevated temperature.