• 방사성폐기물학회지
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• 제17권4호
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• pp.389-403
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• 2019

Large amounts of concrete waste are likely to arise from the decommissioning of a Kori-1 nuclear power plant. Several studies have been conducted on decommissioning concrete waste in recent decades, however, they have been limited to contaminated concrete issues or were small pilot-scale experiments. This study constructed two industrial-scale models of on-site concrete waste management for clean as well as contaminated concrete. To evaluate the performance of both the models, simulations were conducted using the Flexsim software. The concrete particle size distribution of Kori-1 and concrete processor properties based on widely used construction equipment were used as sources of input data for the simulations. It was observed that it may take over two years to complete the on-site concrete management processes owing to the performance of existing processors. In addition, it was demonstrated that it is essential to identify bottlenecks in the system and enhance the performance of the relevant processors to avoid delays of the decommissioning schedule. Our results suggest that this novel approach can contribute to developing schedules or expediting delayed activities in the Kori-1 decommissioning project.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2003년도 봄 학술발표회 논문집
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• pp.223-228
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• 2003

Recently, owing to the deterioration of reconstruction and the construction, much of the construction waste is discharged in our construction field, and the amount of construction waste is rapidly increased. These waste are raised to financial and environmental problems, so the method of reusing waste concretes has been studied and carried out many direction. Especially being want of resources, if waste concrete could be recycled as aggregates for concrete, it will contribute to solve the exhaustion of natural aggregate, in terms of saving resources and protecting environment. This study is that the mechanical properties of concrete with recycled coarse aggregate were investigated for types of mineral admixture and the substitution of recycled coarse aggregate. The result of this study, in case of using mineral admixture, the property of fresh concrete was rised. And the property of harden concrete for the substitution ratio of recycled coarse aggregate was decreased. But the property of concrete with mineral admixture was better than that of concrete used only cement.

• 한국농공학회논문집
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• 제53권6호
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• pp.59-65
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• 2011

This study was performed to evaluate the compressive and flexural strength, void ratio and permeability coefficient used powdered waste glass, $CaCO_3$, recycled coarse aggregate and unsaturated polyester resin to find optimum mix design of permeable polymer concrete for pavement. The compressive and flexural strength of permeable polymer concrete for pavement using powdered waste glass were in the range of 16.8~19.7 MPa and 4.7~6.1 MPa, respectively. it was satisfied the regulation of permeable concrete for pavement (18 MPa and 4.5 MPa). The void ratio and permeability coefficient were decreased with increasing the powdered waste glass, respectively. The void ratio and permeability coefficient were satisfied national regulation of permeable concrete for pavement (8 % and $1{\times}10^{-2}$ cm/s). In addition, this study found out that required amount of binder was decreased with increasing the powdered waste glass. This fact is expected to have economical effects during the use of powdered waste glass in the manufacture of permeable polymer concrete for pavement. Accodingly, the powdered waste glass can be used for permeable concrete material.

• Advances in materials Research
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• 제12권4호
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• pp.331-349
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• 2023

Foam concrete can be considered as environmental friendly material due to its low weight, its minimal cost and a possibility to add waste materials in its production. This paper investigates the possibility of producing foam concrete with waste glass as powder and aggregate. Then, the effect of using waste glass on strength and drying shrinkage of foam concrete was examined. Also, the effect of incorporating polypropylene fibers (12 mm length and proportion of 0.5% of a mix volume) on distribution of waste glass as coarse particles within 1200 kg/m³ foam concrete mixes was evaluated. Waste glass was used as powder (20% of cement weight), as coarse particles (25%, 50% and 100% instead of sand volume) and as fine particles (25% instead of sand volume). From the results, the problem of non-uniform distribution of coarse glass particles was successfully solved by adding polypropylene fibers. It was found that using of waste glass as coarse aggregate led to reduce the strength of foam concrete mixes. However, using it with polypropylene fibers in combination helped in increasing the strength by about 29- 50% for compressive and 55- 71% for splitting tensile and reducing the drying shrinkage by about (31- 40%). In general, not only the fibers role but also the uniformly distributed coarse glass particles helped in improving and enhancing the strength and shrinkage of the investigated foam concrete mixes.

• 공업화학
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• 제30권6호
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• pp.707-711
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• 2019

The feasibility of waste concrete as a catalyst for the effective pyrolysis of polyethylene terephthalate (PET) was examined using thermogravimetric (TG) and pyrolyzer-gas chromatography/mass spectrometry (Py-GC/MS) analyses. TG analysis results indicated that the maximum decomposition temperature of PET is not altered by the use of waste concrete, showing similar values (407 ℃ and 408 ℃ at 5 ℃/min). Meanwhile, the volatile product distribution data obtained from the Py-GC/MS analysis revealed that the use of waste concrete promoted the deoxygenation reaction via converting the oxygen containing products such as benzoic acids, benzoates, and terephthalates to valuable deoxygenated aromatic hydrocarbons including benzene, toluene, ethylbenzene, and styrene. This suggests that the waste concrete can be used as a potential catalyst for the production of valuable aromatic hydrocarbons from PET pyrolysis.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2002년도 봄 학술발표회 논문집
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• pp.329-334
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• 2002

The present age, it has been often reported that recycling of wasted glasses should he a great topic in related business circles. For the enviromental reasons, a public institution are looking for the ways of recycling these waste glasses. First of all, the purpose of this research is to recycle crushed and powdered waste glasses by substituting for the cement in mortar and concrete. the optimum replacement ratio of Powdered Waste Glasses(PWG) can be obtained from the pilot test results. Secondary, we made advances in recycling of waste glasses as recycled to make secondary concrete products. so, we manufactured concrete brick, block and interlocking block for side walk contained powdered waste glasses. finally, we compare properties among of concrete products to slove the economical and environmental problems.

• Advances in concrete construction
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• 제13권 2호
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• pp.133-152
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• 2022

Ecological issues such as natural resource reduction and enormous waste disposals are increasingly leading in developing civilization toward sustainable construction. The two primary environmental issues are the depletion of natural resources and the disposal of trash in open landfills. Waste steel fiber (WSF) was investigated for usage as a cement-based concrete (CBC) constituent in this research. Recycling waste fibers both makes cement composites more long and cost-effective, also aids in pollution reduction. The objective of this study is to analyze the impacts of waste fiber on the fresh and mechanical features of concrete using recycled additives. A comparative research on the durability and mechanical qualities of fiber-reinforced concrete (FRC) constructed with natural aggregates was conducted for this aim. The obstacles to successful WSF recycling methods application in the building industry have been investigated, resulting that CBCs with these fibers make an economic and long lasting choice to deal with waste materials. The workability of fiber enhanced concrete was found to be comparable to that of normal concrete. Fibers have a considerable impact on the splitting tensile strength, flexural and compressive strength of recycled concrete. Fiber may enhance the water permeability. When the WSF content is 0.6 kg/m3, the water absorption is nearly half. Fibers would have no effect on its permeability.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2015년도 추계 학술논문 발표대회
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• pp.128-129
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• 2015

Recently, a number of problems due to the CO₂ emissions are occurred. Therefore, it is a movement to restrict this activity. The research is being carried out steadily for recycling waste concrete from the cement paste based fine powder, which accounts for over 60% of construction waste as a recycled cement. In this study, the conclusion was obtained as a result of the research conducted, and then, replacing the main material of cement concrete to solve the above problem by reducing the amount of cement used Waste Concrete Powder. The more concrete results page replacement ratio of fine powder increases, the flow value of the concrete is lowered, the strength was remarkably reduced when the page Concrete Powder.

• 방사성폐기물학회지
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• 제11권4호
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• pp.271-280
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• 2013

원자력 발전소와 연구시설의 해체 시 다량의 오염된 방사성 콘크리트 폐기물이 발생한다. 현재 국내에는 연구로 1, 2호기의 해체와 제염사업이 진행 중이며, 약 800여 드럼 (200 L)의 콘크리트 폐기물이 발생하였다. 이들 방사성 콘크리트 폐기물은 최종처분을 위해 200 L 드럼에 덩어리 크기의 콘크리트를 채우고, 시멘트 모르타르 형태로 제조한 입자상 폐기물로 빈 공간을 채우며 혼용 고정화 및 안정화하는 일련의 과정이 필요하다. 이에 본 연구에서는 콘크리트 폐기물, 물, 시멘트의 최적의 혼합비율을 찾고, 처분장 폐기물 인수기준에 준하기 위한 고화체의 특성을 평가하였다. 모르타르 유동도, 고화체 압축강도, 침출에 대한 안정성, 열 저항성 등의 인자에 따라 평가한 결과, 콘크리트 폐기물, 물, 시멘트의 배합비 75:15:10wt%에서 평가인자 기준에 도달하였으며, 콘크리트 폐기물 75%에 미분말 콘크리트 폐기물을 최대 40wt%까지 포함시켜 시멘트 고화체를 제조한 경우에도 압축강도를 만족하였다. 입자의 충진 밀도의 증가로 scale-up실험에서는 75:10:15wt%의 배합비에서 작업도 및 압축강도 범위를 만족하였다.

• 콘크리트학회논문집
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• 제14권6호
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• pp.1032-1039
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• 2002

폐유리병을 콘크리트용 재료로서 재활용하는 것은 환경적으로나 경제적으로 큰 이점을 가지고 있어 미국ㆍ일본 등지에서는 이미 폐유리에 대한 재활용이 광범위하게 진행되고 있으며, 폐유리의 가공설비 및 시공기술도 상당한 기술축적이 이루어져 있다. 그러나 국내의 경우 폐유리를 사용한 콘크리트의 역학적 특성에 관한 실증적 자료는 전무한 실정이다. 본 연구에서는 폐유리 혼입률(잔골재 대체비 20vo1.%, 40vo1.%)과 강섬유 혼입률(0.5~ 1.5vol.%)에 따른 콘크리트의 역학적 특성을 분석하였다. 연구결과 폐유리를 사용한 강섬유보강 콘크리트의 워커빌리티는 폐유리 및 강섬유 혼입률이 증가할수록 감소하는 경향을 나타내었으며, 폐유리를 혼입한 콘크리트의 인장강도, 휨강도 및 휨인성은 강섬유 혼입률이 증가할수록 크게 증대됨을 확인하였다. 이들 시험결과로부터 적정 강섬유와 폐유리 혼입량은 각각 1.0vol.%와 20vo1.%로 판단된다.