• Proceedings of the Korean Institute of Building Construction Conference
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• 2015.11a
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• pp.160-161
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• 2015

This research reviewed the characteristics of waste concrete sludge occurred from recycled aggregate producing process and the physical and mechanical properties of the mortar incorporated the pulverized the waste concrete sludge. From the results of the experiment, as the replacement ratio of waste concrete sludge powder was increased, the dosage of superplasticizer to satisfy the target flow of 200 ± 10 was increased, and the compressive and flexural strengths were decreased. On the other hand, when the sludge powder replacement ratio was 25 %, outstanding performance of general characteristics of mortar was obtained while it was lower than Plain mixture, thus, further detail study on various replacement ratios of waste concrete sludge powder is needed.

• Proceedings of the Korea Concrete Institute Conference
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• 2001.11a
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• pp.1065-1070
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• 2001

The present age, it has been often reported that recycling of wasted glasses should be a great topic in related business circles. For the enviromental reasons, a public institution are looking for 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.

• Advances in concrete construction
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• v.4 no.4
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• pp.263-281
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• 2016

Concrete continues to be the most consumed construction material in the world, only next to water. Due to rapid increase in construction activities, Construction and Demolition (C&D) waste constitutes a major portion of total solid waste production in the world. It is important to assess the amount of C&D waste being generated and analyse the practices needed to handle this waste from the point of waste utilization, management and disposal addressing the sustainability aspects. The depleting natural resources in the current scenario warrants research to examine viable alternative means, modes and methods for sustainable construction. This study reports processing Recycled Coarse Aggregates (RCA) using a rod mill, for the first time. Parameters such as amount of C&D waste for processing, nature of charge and duration of processing time have been optimized for obtaining good quality RCA. Performance of RCA based concrete and performance enhancement techniques of 50% RCA based concrete are discussed in this paper.

• Magazine of the Korean Society of Agricultural Engineers
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• v.44 no.3
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• pp.85-91
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• 2002

This study is performed to evaluate characteristics of plantable concrete using waste stone and stone dust. The test result shows that the void ratio is decreased as the size of waste stone smaller and the content of stone dust increased. The strength of neutralized plantable concrete is decreased by approximately 4∼5% than that of the normal plantable concrete. The reduction effect of pH value is achieved by chemical treatment. Also, the plant is grown well with increase of the void ratio and size of waste stone.

• Journal of Industrial Technology
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• v.16
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• pp.25-30
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• 1996

The waste foundry sand might be recycled in concrete, resulting in energy saving and environmental protection. An half Factorial Experiments were performed with the variables of W/C ratio, S/A, Sand/Waste foundry sand ratio and Slump as a preliminary study for optimum mix design of concrete. The results show that then W/C ratio is the most important factor to the concrete strength. The substitute of waste foundry sand up to 30% has little influence, saying that it can substitute the fine aggregate without damaging the concrete properties.

• International Journal of Concrete Structures and Materials
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• v.18 no.2E
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• pp.125-132
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• 2006

Waste glass has been increasingly used in industrial applications. One shortcoming in the utilization of waste glass for concrete production is that it can cause the concrete to be weakened and cracked due to its expansion by alkali-silica reaction(ASR). This study analyzed the ASR expansion and strength properties of concrete in terms of waste glass color(amber and emerald-green), and industrial by-products(ground granulated blast-furnace slag, fly ash). Specifically, the role of industrial by-products content in reducing the ASR expansion caused by waste glass was analyzed in detail. In addition, the feasibility of using ground glass for its pozzolanic property was also analyzed. The research result revealed that the pessimum size for waste glass was $2.5{\sim}1.2mm$ regardless of the color of waste glass. Moreover, it was found that the smaller the waste glass is than the size of $2.5{\sim}1.2mm$, the less expansion of ASR was. Additionally, the use of waste glass in combination with industrial by-products had an effect of reducing the expansion and strength loss caused by ASR between the alkali in the cement paste and the silica in the waste glass. Finally, ground glass less than 0.075 mm was deemed to be applicable as a pozzolanic material.

• Nuclear Engineering and Technology
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• v.42 no.2
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• pp.175-182
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• 2010

As part of a fundamental study on the volume reduction of contaminated concrete wastes, the separation characteristics of the aggregates and the distribution of the radioactivity in the aggregates were investigated. Radioisotope $^{60}Co$ was artificially used as a model contaminant for non-radioactive crushed concrete waste. Volume reduction for radioactively contaminated dismantled concrete wastes was carried out using activated heavy weight concrete taken from the Korea Research Reactor 2 (KRR-2) and light weight concrete from the Uranium Conversion Plant (UCP). The results showed that most of the $^{60}Co$ nuclide was easily separated from the contaminated dismantled concrete waste and was concentrated mainly in the porous fine cement paste. The heating temperature was found to be one of the effective parameters in the removal of the radionuclide from concrete waste. The volume reduction rate achieved was above 80% for the KRR-2 concrete wastes and above 75% for the UCP concrete wastes by thermal and mechanical treatment.

• Proceedings of the Korea Concrete Institute Conference
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• 2001.05a
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• pp.49-54
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• 2001

Using waste glass in concrete can cause crack and strength loss by the expansion of alkali-silica reaction(ASR). In this study, ASR expansion and properties of strength were analyzed in terms of brown waste glass content, and fibers(steel fiber, polypropylene fiber) and fiber content for reduction ASR expansion due to waste glass. In this accelerated ASTM C 1260 test of waste glass, pessimum content can not be found. Also, when used the fibers with waste g1ass, there is an effect on reduction of expansion and strength loss due to ASR between the alkali in the cement paste and the silica in the waste glass. Specially, adding 1.5 vol.% of steel fiber to 20% of waste glass the expansion ratio was reduced by 40% and flexural strength was developed by up to 110% comparing with only Waste glass ( $80^{\circ}C$ $H_{2}$ O curing).

• Proceedings of the Korea Concrete Institute Conference
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• 1999.10a
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• pp.139-142
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• 1999

The purpose of this experimental research is to investigate the mechanical properties of ordinary strength and high strength concrete containing waste glass powder. For this purpose, after production of concrete containing waste glass powder for different unit weight of binder and placement ratio of waste glass powder, optimum mixing proportions of them was determined, and then mechanical properties such as static modulus of elasticity as well as compressive, tensile and flexural strength were tested and analyzed for concrete produced according to optimum mixing proportions. As a result, the concrete containing waste glass powder has as excellent workability and strength, it's strengths are analogus to those of silica fume, it's workability is somewhat better than that of silica fume.

• Advances in concrete construction
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• v.6 no.3
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• pp.221-243
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• 2018

Utilization of mine waste rocks and tailings in concrete as aggregates will help in sustainable and greener development. The literature shows the potential use of iron ore tailings as a replacement of natural fine aggregates. As natural sand reserves are depleting day by day, there is a need for substitution for sand in concrete. A comprehensive overview of the published literature on the use of iron ore waste and tailings and other industrial waste in concrete is being presented. The effect of various properties such as workability, compressive strength, split tensile strength, flexural strength, durability and microstructure of concrete have been presented in this paper.