• Explosives and Blasting
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• v.9 no.2
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• pp.19-30
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• 1991

The trend of Radio active waste disposal project is generally to choose The Rock Cavern type because it is the most safest and easy to get concent from The neighbor hood. On the Construction of rock Cavern for R -A. W.0 has to take care follows ; The first of all, to survey rock crack formation. 2nd, The Movement of Underground water. 3rd, Nuclear and Geochemical problems. 4th, to examine physical feature of rocks ets.

• Advances in concrete construction
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• v.5 no.3
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• pp.201-219
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• 2017

With the rapid growth in construction sector, it becomes all the more important to assess the amount of Construction and Demolition (C&D) waste being generated and analyze the practices needed to handle and use this waste before final disposal. This serves waste management and disposal issues, paving way to waste utilization in construction industry from the sustainability point of view. C&D waste constitutes a major bulk of total solid waste produced in the world. In this work, an attempt is made to study the performance of concrete using water soaked Recycled Coarse Aggregates (RCA) in replacement levels of 0%, 25%, 50%, 75% and 100% to Natural Coarse Aggregates (NCA). Experiments were designed and conducted to study the performance of RCA based concrete. Further suitable performance enhancement techniques to RCA based concrete were attempted, to achieve compressive strength at least equal to or more than that for no RCA based concrete (control concrete). Performance enhancement study is reported here for 50% and 100% RCA based concretes. All four techniques attempted have given favorable results encouraging use of RCA based concretes with full replacement levels, to adopt RCA based concrete in structural applications, without any kind of concern to the stake holder. Further attempts have also been made to use Recycled Fine Aggregates (RFA) with appropriate modifications to serve as fine aggregates in mortar and concrete. Using RFA blended with river sand fractions as well as RFA with Iron Ore Tailings (IOT) fractions, have given good results to serve as fine aggregates to the extent of 100% replacement levels in mortars and concretes.

• Journal of Korea Port Economic Association
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• v.17 no.1
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• pp.159-180
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• 2001

The quantity of waste has been increased due to the increase in population and consumption after industrialization. Accordingly it caused the urban environmental problems, the lack of landfill and the pollution around the landfill. Thus, it is necessary to research the adequate alternative in the long-term. In case of Japan, areas and quantities of landfills at sea are more great than those of landfills in land. And investigating our condition, landfills of the metropolitan area in land are to be fully filled with wastes up to 2020 and be closed. In this research, construction of landfill sites at sea is suggested as the alternative waste disposal method and it is suggested that in our country, the suitable landfill sites of the metropolitan area are the regions around Jangbong-do Island and Muei-do Island. It is expected that the best way to transport wastes is to transport through Kyungin canal from the middle collection center to the lower Han River. Rough cost for construction of landfill at sea, if it is used for 50 years, is expected to be 2 trillion won and total time to construct the landfill is expected to be 10 years. Many studies concerning to this research proposal are to be performed so that construction of landfills familiar to environment are to be accomplished.

• Tunnel and Underground Space
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• v.32 no.2
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• pp.107-119
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• 2022

Excavation-Disturbed Zone (EDZ) is an important design factor in constructing final disposal facilities for spent nuclear fuel, since EDZ affects mechanical stability including a spacing between disposal holes, and the hydraulic properties within EDZ plays a significant role in estimating in-flow rate of groundwater as well as a subsequent corrosion rate of a canister. Thus, it is highly required to characterize in-situ EDZ with precision and control the EDZ occurrence while excavating disposal facilities and constructing relevant underground research facilities. In this report, we not only reviewed EDZ-related researches carried out in the ONKALO facility of Finland but also examined appropriate methods for field inspection and quality control of EDZ occurrence. From the review, GPR can be the most efficient method for in-situ characterization of EDZ since it does not demand drilling a borehole that may disturb a surrounding environment of caverns. And the EDZ occurrence was dominant at a cavern floor and it ranged from 0 to 70 cm. These can provide useful information in developing necessary EDZ-related regulations for domestic disposal facilities.

• Proceedings of the Korea Society for Energy Engineering kosee Conference
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• 2004.05a
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• pp.353-358
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• 2004

In recent, the trends in national energy Policy are established in the context of the integrated risk estimation for various national electricity generating options. The approach takes account of health, environmental, economic, and social aspects of electricity generation systems. In the present work, nuclear, coal, and LNG sources are chosen because these hold more than 90% of national total electricity generation in a descending order. A life cycle assessment (LCA) methodology is used for comparing environmental impacts of these options during the life cycle such as construction, operation as well as disposal stages. Here, the LCA consists of life cycle inventory analysis, classification/selection process of impact categories, characterization process, and normalization process of each category. LCA can be an useful tool for environmental impact assessment of future national energy options. At the planning stage of future energy Policies, the results of LCA would be taken into consideration. According to data update at the construction and disposal stages, the LCA needs to be conducted iteratively.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2016.05a
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• pp.43-44
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• 2016

Large amount of dredged sea soil is produced in southeast seashore region in during harbor maintenance. Disposal of dredged sea soil has become difficult due to the environmental regulation. Therefore, disposal of dredged sea soil method is to landfill. But, the capacity of the landfill limit state and if the size of the dredged sea soil is in the range of silt or clay, it cannot be used as reclamation material because ground subsidence occur. In this study, analyzed the pozzolanic activity of dredged sea soil. Analysis of the results showed a pozzolanic activity of dredged sea soil. In addition, incorporation of heat treated dredged sea soil increase both 28 and 56 day compressive strength of mortar specimen.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2006.11a
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• pp.1-4
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• 2006

Because do placing joint after smallest $1{\sim}3$ day about concrete that is placed beforehand in field, it is difficult that remove laitance happening harden concrete. This laitance happens a problem of bond properties, deterioration in strength. In this research got following conclusion as result that do research about bond properties the way of disposal placing joint. Air Jet is loft interior and exterior. Water Jet appeared that laitance Removal Capacity is superior to dimension within 5%. Deterioration in strength is measured 37% by splitting tensile strength test result by laitance. Deterioration in strength by laitance do more than 30% that removal of laitance is predicted must consist necessarily at concrete horizontality placing joint stroke.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2023.05a
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• pp.305-306
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• 2023

Recently, as the radioactive waste disposal facility becomes scarce, the importance of efficient disposal of waste from nuclear power plants is increasing. This study was conducted to utilize radioactive waste concrete powder as solidifying agent for radioactive waste treatment. Paste with an age of more than one year was used with a disk mill to have a particle size of 150㎛ or less, and treated at temperatures of 500℃, 600℃ and 700℃ for 2 hours. In order to simulate the radioactive cement powder, aqueous solutions of Di-water, CsCl 1M, SrCl₂ 1M and CoCl₂ 1M were used as blending water at W/C 0.7 and to improve fluidity, polycarboxylate type superplasticizer was used at 0.4 wt.% based on the weight of recycled cement paste powder. Characterisation was carried out using vicat method, strength and density.

• Magazine of the Korean Society of Agricultural Engineers
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• v.44 no.3
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• pp.122-135
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• 2002

Although fly ash possesses viable engineering properties, an overwhelming majority of fly ash from coal combustion is still placed in storage or disposal sites. Similarly, sludges generated from various water treatment operations are predominantly subjected to the fate of land disposal. To prepare sludges fur land disposal typically requires time consuming dewatering schemes, which can become extremely difficult to execute depending upon the composition of the sludge and its affinity for water. This study was undertaken to reuse fly ash and sludge as construction materials. This paper includes geotechnical properties of fly ash and fly ash-lime-sludge mixture and results of compaction test, UU-test, falling head test, leaching test and CBR test. The effect on mixing fly ash with sludge and lime and the effect of curing period and the results are obtained from this test.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2001.04a
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• pp.259-266
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• 2001

This paper presents the results of a structural analysis to determine design variables such as the inner basket array type, and thicknesses of the outer shell and the lid and bottom of a spent nuclear fuel disposal canister. The canister construction type introduced here is a solid structure with a cast iron insert and a corrosion resistant overpack, which is designed for the spent nuclear fuel disposal in a deep repository in the crystalline bedrock, entailing an evenly distributed load of hydrostatic pressure from the groundwater and large swelling pressure from the bentonite buffer. Hence, the canister must be designed to withstand these large pressure loads. Many design variables may affect the structural strength of the canister. In this study, among those variables, the array type of inner baskets and thicknesses of outer shell and lid and bottom are attempted to be determined through a linear static structural analysis. Canister types studied here are one for the pressurized water reactor (PWR) fuel and another for the Canadian deuterium and uranium reactor (CANDU) fuel.