• Proceedings of the Korea Concrete Institute Conference
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• 2002.05a
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• pp.693-698
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• 2002

The production accounts of domestic by-product is increased after 1990's. It is worried about the life reduction of dump land, as dump land's capacity have reached to limitation and the amount of construction industrial wastes is going higher. Recently, recycling aggregates could be gained from the reconstruction works using recycle process. And the study and research of recycle concretes developed concrete application methods. It could put some outcome of studies to practical use for concrete products. The methods of crushing waste concrete are going diverse. In this study, the fundamental experiments and recycling application is investigated and analyzed with use of recycling aggregate which made of mechanical crush and underwater electrical impact crush. and the difference between underwater electrical impact crush, mechanical crush and natural aggregates is studied.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2022.11a
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• pp.27-28
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• 2022

In this study, the mechanical properties of resource-recycling concrete containing concrete sludge waste as main materials was compared depending on whether supercritical CO2 curing was applied for the realization of CCU technology. After supercritical CO2 curing, the compressive strength of the steam-cured specimen was lowered, but it was confirmed that the compressive strength of the underwater-cured specimen was improved.

• Journal of the Korean Recycled Construction Resources Institute
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• v.10 no.4
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• pp.465-474
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• 2022

Research on the recycling of waste concrete has been conducted mainly focusing on the production of high-quality recycled ag g reg ate, and as a result, standards and specifications for recycled ag g reg ate have been established. However, in the case of waste concrete powder, although a lot of research on its utilization has been conducted in Korea, an innovative technology leading to commercialization has not yet been announced. Recently, research on technology using waste concrete powder as a raw material for clinker or cement has been actively conducted in major overseas advanced countries. This study investigated the overseas cases with regard to high value-added recycling technology and commercialization trend of waste concrete powder for carbon neutrality in cement and concrete industries. A number of studies have reported that it is essential to completely separate the aggregate and hydrated cement paste fraction for recycling of waste concrete powder. Also in major foreig n countries such as EU and USA, commercialization and standardization of using waste concrete powder as a raw material for clinker or a additive for cement are now in progress beyond the R&D stage. Therefore, Research and standardization for recycling of waste concrete powder should be urgently carried out from the perspective of carbon neutrality in Korea.

• Journal of the Korea Organic Resources Recycling Association
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• v.20 no.2
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• pp.27-35
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• 2012

Concrete produced from the construction wastes has been largely used as the recycled aggregate. These wastes, however, is mostly used as filling materials. For any recycled aggregate like waste concrete to be used as normal construction materials, it is necessary to actively find out the proper market places as much as possible with the improved quality. In this study, we have investigated the present status on the occurrence and treatment of both domestic and abroad construction wastes, and also the recycling status and related legislation with some inhibitory factors. Based on these investigations, we suggested some effective ways to increase the recycling of construction wastes.

• Proceedings of the Korea Concrete Institute Conference
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• 2006.11a
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• pp.517-520
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• 2006

The production of recycling aggregate is used to process in the crushing that recycling aggregate isn't perfect the concrete aggregate in Korea. This study is examine to the properties of recycling aggregate used method of trituration. Test item is the fineness, density and percent of absorptance, solid volume percentage of aggregate. The result is that first, the method of trituration is excellent to increase the time of trituration and steel ball but decrease washing water. Second, method of trituration is improve to the properties of recycling aggregate but aggregate of production is irregularity. And method of trituration have to study of the many test items.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2001.11a
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• pp.58-63
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• 2001

Recently, it has been often reported that recycling of wasted glasses should be a great topic in related business circles. For the environmental reasons, a public institution are looking fur the ways of recycling these waste glasses. Consequently, the purpose of this research is to recycle crushed and powdered waste glasses by substituting for the cement in mortar and concrete. First of all, the optimum replacement ratio of Powdered Waste Glasses(PWG) can be obtained from the pilot test results. Secondary, we make advances in recycling of waste glasses as recycled to make secondary concrete products. So, we manufactured concrete brick and block contained powdered waste glasses by through mortar pilot test.

• Proceedings of the Korean Institute of Resources Recycling Conference
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• 2005.05a
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• pp.109-112
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• 2005

The electrical pulse separation of concrete samples for the recycling purpose has been investigated by the electrical disintegration method using the discharged high voltageimpulse. First, when the consumed energy increased in electrical crushing, fracture section area increased clearly. This result suggests that crushing energy was consumed efficiently. Secondly, when conventional crushing after electrical disintegration is compared with only conventional crushing, gravels are more stable after electrical crushing. Thus, electrical crushing makes it easy to recover gravels from wasted concrete. In the next year, more efficient recovery of gravel for wasted concrete by electrical disintegration will be investigated. Thus, actual wasted concrete crushing by electrical separation and combination of conventional crushing will be carried out.

• Journal of the Korea Institute of Building Construction
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• v.5 no.3 s.17
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• pp.109-116
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• 2005

Recently, there have been many studies seeking towards the utilization of cementitious powder from concrete waste as recycled cement. However, most of the studies actually have been researches about the reuse of mortar or paste, not concrete waste. In fact, either mortar or paste is quite different from a real concrete waste in terms of age and mixture. Thus the purpose of this study is to examine basic physical properties of recycled cement, manufactured with cementitious powder from concrete waste, and analyze differences in chemical and hydraulic properties of the cement and its tested model. As a result of the chemical analysis, recycle cement is composed mainly of CaO and $SiO_2$, and that it is even lower in the content of CaO than Portland cement, which is also supported by previous studies. But, Differently from previous studies, calcining temperature of 650 was found an optimal condition under which cementitious powder from concrete waste could restore its hydraulic properties.

• Journal of the Korean Recycled Construction Resources Institute
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• v.4 no.4
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• pp.477-482
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• 2016

This study investigates the expressions characteristics of compression strength depending on the condition of fresh concrete and cured concrete by producing Non-cement mortar and concrete only with solidified sludge in the dehydrated cake form, recycled concrete and premixed materials(BS, FA) in order to actively use remicon recycling water as resources, rather than as construction waste material. After treating wastewater of pH 12.5 or more with alkali activator and after promoting BS hydration reaction, the amount of BS inflow was found to be increased and compression strength was increased accordingly: these results coincide with the analysis results of TG-DTA and SEM.

• Magazine of RCR
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• v.8 no.3
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• pp.20-24
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• 2013