• Proceedings of the Korea Concrete Institute Conference
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• 2003.05a
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• pp.7-12
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• 2003

In scrapped material field, about ten millions ton of waste plastic materials are produced in korea. However recycling rate of waste plastic materials have above 25%. Therefore, it is urgently needed that they are used as recycled materials in order to prevent environment pollution and grain economic profits. In this paper, physical and mechanical properties of light weight concrete using waste plastic materials for aggregates are described in order to develop a light weight concrete with the aggregate made from waste plastic goods, it was carried out many experiments on mix proportion and strength. According to the experimental results, high-strength mortar was necessary to make light weight concrete using aggregate of waste plastic materials. Especially, considering the side of recycling of plastic wastes, it is recommended that recycled aggregates made from waste plastic materials is applied to light weight concrete.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2012.05a
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• pp.283-286
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• 2012

According to increase of the waste concrete occurrence, recycling has being important more and more. This study is to recycle the waste concrete powder, which is occurred in dry-process during recycling of construction waste. We have tried the waste concrete powder to apply as the replacement of the silica powder in cement extruding product. As a result, it is satisfied that the autoclave cured pannel of 50% replacement ratio of waste concrete powder staisty the level of the flexural strength of 14MPa stipulated by "KS F 4735 Extruding concrete panel" was the same thermal properties as base specimen.

• Journal of the Korean Recycled Construction Resources Institute
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• v.4 no.2
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• pp.82-89
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• 2009

According to the great city development and the rapid growth of redevelopment project, waste concrete emission has been increased. Waste concrete powder is one of the by-product originated from the recycling of the waste concrete. The more making high quality recycled aggregate to use aggregate for concrete, the more waste concrete powder is producted relatively. Therefore, to realize the total recycling of waste concrete, development of recycling technology for waste concrete powder need very much. This technical note present the discharged process and the various properties of waste concrete powder. As the results, on the average, the maximum particle-size of waste concrete powder is less than $600{\mu}m$, and oven-dry density is less than $2.5g/cm^3$. And waste concrete powder contains more than 50% of $SiO_2$, 30% of CaO and 10% of $Al_2O_3$. Thus qualities of waste concrete powder is lower than those of high quality raw material for concrete. However, if it is processed by grading to the purpose, it will be used as resource of raw materials for construction field.

• Journal of the Korean Society of Safety
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• v.18 no.1
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• pp.76-80
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• 2003

There will be a big problem in disposing of waste tie coming from the cars. Because many of these have been thrown away to the field and environmentally polluted. New, We need to find out how to dispose or recycle these waste material. It is thought that recycling this material especially mixing with concrete will be a good idea. This study is focused how each material do its behavior due to the size of waste type particle and its amount into concrete material. 0.4mm-10mm range of particle has been applied to the material : Also, 1.0%, 1.5%, 2.0% range of tyre particle proportion has been applied to make cylinder molds. The concrete mold with waste-tyre particle has vibration-absorbing ability. It is found that 0.4 -0.6mm particle mixing concrete has been more solid organized. And this waste tyre material could be applied to the general concrete, it is found.

• Proceedings of the Korea Concrete Institute Conference
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• 1996.10a
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• pp.58-63
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• 1996

The waste foundry sand might be recycled in concrete, resulting in energy saving and environmental protection. An half Factorial Exprements 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 the 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.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.19 no.2
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• pp.267-270
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• 2021

Long-term experiments have been conducted on two important safety issues: long-term durability of a concrete barrier with the steel reinforcements and gas generation from low-and intermediate-level wastes in an underground research tunnel of a radioactive waste disposal facility. The gas generation and microbial communities were monitored from waste packages (200 L and 320 L) containing simulated dry active wastes. In the concrete experiment, corrosion sensors were installed on the steel reinforcements which were embedded 10 cm below the surface of concrete in a concrete mock-up, and groundwater was fed into the mock-up at a pressure of 2.1 bars to accelerate groundwater infiltration. No clear evidence was observed with respect to corrosion initiation of the steel reinforcement for 4 years of operation. This is attributed to the high integrity and low hydraulic conductivity of the concrete. In the gas generation experiment, significant levels of gas generation were not measured for 4 years. These experiments are expected to be conducted for a period of more than 10 years.

• Nuclear Engineering and Technology
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• v.55 no.2
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• pp.530-545
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• 2023

As an alternative to conventional management options for a lot of concrete waste from decommissioning of nuclear power plants, a set of scenarios for controlled recycling of decommissioning concrete waste as engineered barriers of a radioactive waste repository was proposed, and a comprehensive safety assessment model and framework covering both pre-and post-closure phases was newly developed. The new methodology was applied to a reference vault-type repository, and the ratios of derived concentration limits to unconditional clearance levels of eighteen radionuclides for controlled recycling were provided for three sets of dose criteria (0.01, 1, and 20 mSv/y for the pre-closure and 0.01 mSv/y for the post-closure phases). It turns out that decommissioning concrete waste whose concentration is much higher than the unconditional clearance level can be recycled even when the dose criterion 0.01 mSv/y is applied. Moreover, a case study on ABWR bio-shield shows that the fraction of recyclable concrete waste increases significantly by increasing the dose criterion for the radiation worker in the pre-closure phase or the duration of storage prior to recycling. The results of this study are expected to contribute to demonstrating the feasibility of controlled recycling of a lot of decommissioning concrete waste within nuclear sectors.

• Advances in concrete construction
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• v.15 no.1
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• pp.63-74
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• 2023

All production and consumption activities produce wastes, which often cause damage to our environment and multiple risks to the human health. The valorization of these wastes in concrete technology is a future solution that will allow finding other construction materials sources, optimizing energy consumption and protecting the environment. Among these wastes, there is the marble waste. Every year, huge amount of marble waste is discarded as dust or aggregates form, in open-air storage areas causing serious problems for the environment and public health. In this context, the incorporation of marble waste as a replacement of ordinary aggregates or cement in concrete composition is actively investigated by researchers. This paper presents a comprehensive review of published studies over the last 20 years, dealing the effect of marble waste on fresh and hardened properties of concrete. Most of the studies carried out have used marble waste as dust with substitution rates between 5 and 20%. Besides the economic and ecological benefits, this review showed that marble waste can improve the physical, mechanical and durability properties of concrete. This improvement depends on the form (dust, fine aggregate or coarse aggregate), substitution method (as cement or aggregates replacement) and substitution rate of marble waste. Additionally, the review results showed that the use of 10-15% of marble waste dust as cement substitution can lead to increase the compressive strength.

• Proceedings of the Korea Concrete Institute Conference
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• 1998.10c
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• pp.7-12
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• 1998

The waste sludge is by-produced about 20-30% of total production and arised to the severe problems of this mine's surrounding environmnet. This study was invested the composition of component, particle of size of the waste sludge by Chemical Analysis, X, R, D, Particle Size Analyzer and the physical properties (air content, slump, strength, etc) of concrete when the waste sludge is added into concrete. so, It's recomended the proper content of the waste sludge to be added into concrete. and then, is verified to be applied at batch plant in field. Above the results, the recomeded content of the waste sludge is about 2-4% (about 4-8% in cement) in aggregates and when it's added the recomended content, they are detected to be more or less changed the physical properties of concrete, ( equally strength and durability, little less air con tent, little increased shinkage, etc). but the application of the recomended content don't arise the problem of the basic quality control of concrete and physical properties.

• Proceedings of the Korea Concrete Institute Conference
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• 1994.04a
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• pp.197-202
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• 1994

This study is designed for analyzing the physical properties of grading, shape, specific gravity and etcetera of mine-waste as the aggregate of concrete when mine waste is crushed by jaw crusher, and is aimed presenting the using the possibility, content and reference data for the quality control of practical use on the concrete using the mine-waste aggregate.