• 한국방사성폐기물학회:학술대회논문집
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• 한국방사성폐기물학회 2017년도 추계학술논문요약집
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• pp.113-114
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• 2017

• Computers and Concrete
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• 제28권6호
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• pp.567-583
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• 2021

The use of waste materials as a binder or aggregate in the concrete mixture is a great step towards sustainability in the construction industry. Waste rubber (WR) can be used as coarse and fine aggregates in concrete and improves the crack resistance, impact resistance, and fatigue life of the produced concrete. However, the mechanical properties of rubberized concrete degrade significantly by replacing the natural aggregate with WR. To have accurate estimations of the mechanical properties of rubberized concrete, two machine learning methods consisting of artificial neural network (ANN) and neuro-fuzzy system (NFS) were served in this study. To do this, a comprehensive dataset was collected from reliable literature, and two scenarios were addressed for the selection of input variables. In the first scenario, the critical ratios of the rubberized concrete and the concrete age were considered as the input variables. In contrast, the mechanical properties of concrete without WR and the percentage of aggregate volume replaced by WR were assumed as the input variables in the second scenario. The results show that the first scenario models outperform the models proposed by the second scenario. Moreover, the developed ANN models are more reliable than the proposed NFS models in most cases.

• 산업기술연구
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• 제17권
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• pp.227-232
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• 1997

This study was conducted to evaluate durability of concrete which are increasingly demanded recently. Concrete durability properties incorporating waste foundry sand was performed with the variable of W/C ratio, Sand/Waste foundry sand ratio and Air entrainment-Non air entrainment. Cylinder specimens were made and subjected to freezing and thawing cycle at $-18^{\circ}C$ and $4^{\circ}C$. Dynamic modulus of elasticity were evaluated as F/T cycle increase. The results show that decreasing W/C ratio and AE concrete makes improved resistance of freezing and thawing improved. Especially, resistance of freezing and thawing is improved by Fine aggregate/Waste foundry sand ratio which is 50%, 25%, 0% in a row.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2002년도 봄 학술발표회 논문집
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• pp.137-142
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• 2002

The purpose of this study is to develop of recycling cement using the waste concrete powder. For presentation possible of practical use as cement powder, we activated waste-powder at temperatures between 600 and 100$0^{\circ}C$. And we made recycling cement hardening as being added Ca(OH)$_2$ and the others in recycling cement. The result of this study are as follow; 1)According to compressive strength result, it is found setting and hardened. 2)Active waste powder is positive to the pozzolan reaction and is enable to be used as cement.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2011년도 추계 학술논문 발표대회
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• pp.39-40
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• 2011

This study is to analyse possibility cementitious powder from waste concrete as row material of recycled cement. From the results, we ascertained possibility as recycled cement through XRF & XRD of cementitious powder & recycled cement. As a result of the experiment, cementitious powder from waste concrete, which appeared to recovery hydration chemically at the calcining temperature of 700, suggested highly possibility as recycled cement.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2011년도 추계 학술논문 발표대회
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• pp.117-118
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• 2011

South Korea is a ninth greenhouse gas emission nation in the world(2007) and is certainly to perform a duty to conduct reduction role by the Kyoto Protocol in 2013. waste concrete produced in the country is 45 million tons per year and these two issues are being came to the fore as major problems of society. However, if it utilizes wet carbonation system carbon using carbon dioxide and waste concrete as raw material it can expect effect of environmental protection and resource recycling. Furthermore, it can exploit another industry production.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1997년도 가을 학술발표회 논문집
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• pp.190-195
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• 1997

The purpose of this study was to use daily waste incinerated ash, which was reclaimed worthlessly, as substitutes of fine aggregates in concrete. Various kinds of admixture was utilized to strengthen the cement mortar mixed with waste incinerated ash, and altered the curing condition to diminish the rate of expansion. By the results of this experiment, it was possible to produce the lightweight concrete, charactered with the gravity below 1.5 and over 160kg/$\textrm{cm}^2$ compressive strength by replacing all fine aggregates with waste incinerated ash. It was also observed that the low temperature curing condition, lessoned gas exhausts, was effective to increase the strength of cement mortar.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2013년도 추계 학술논문 발표대회
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• pp.76-77
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• 2013

The paper study on the mechanical properties of self-compacting concrete with waste marble powder. A change in the replacement ratio s of waste marble powder was measured compressive strength and slump flow, U-Box. As a results, Slump flow and U-box using waste marble powder tend to increase slump flow and compacting with replacement ratio. As the concrete with a replacement ratio of copper slag up to 10% was found to have a compressive strength superior to that of plain.

• Steel and Composite Structures
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• 제50권5호
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• pp.595-608
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• 2024

In this study, aluminum lathe waste was used by replacing aggregates in certain proportions in order to obtain expansive concrete using recycled materials. For this reason, five different aluminum wastes of 1%, 2%, 3%, 4% and 5% were selected and also reference without aluminum waste was produced. Based on the mechanical tests conducted, which included slump, compression, splitting tensile, and flexural tests, it was evident that the workability of the material declined dramatically once the volume ratio of aluminum exceeded 2%. As determined by the compressive strength test (CST), the CS of concrete (1% aluminum lathe wastes replaced with aggregate) was 11% reducer than that of reference concrete. It was noted that the reference concrete's CS values, which did not include aluminum waste, were greater than those of the concrete that contained 5% aluminum. When comparing for splitting tensile strength (STS), it was observed that the results of STS generally follow the parallel inclination as the CS. The reduction in these strengths when 1% aluminum is utilized is less than 10%. These ratios modified 18% when flexural strength (FS) is considered. Therefore, 1% of aluminum waste is recommended to obtain expansive concrete with recycled materials considering minimum loss of strength. Moreover, Scanning Electron Microscope (SEM) analysis was performed and the results also confirm that there was expansion in the aluminum added concrete. The presence of pores throughout the concrete leads to the formation of gaps, resulting in its expansion. Additionally, for practical applications, basic equations were developed to forecast the CS, STS, and FS of the concrete with aluminum lathe waste using the data already available in the literature and the findings of the current study. In conclusion, this study establishes that aluminum lathe wastes are suitable, readily available in significant quantities, locally sourced eco-materials, cost-effective, and might be selected for construction using concrete, striking a balance among financially and ecological considerations.

• 방사성폐기물학회지
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• 제16권4호
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• pp.441-454
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• 2018

2017년 고리 1 호기 영구정지를 계기로 국내 원자력발전소의 해체가 점차 가시화되고 있다. 앞으로 원전 해체가 본격적으로 추진될 경우 원전 1기 당 약 16만 t의 콘크리트 폐기물이 발생될 것으로 예측되었으며, 이들 콘크리트 폐기물은 대부분 오염준위가 매우 낮아 자체처분 대상으로 고려될 수 있다. 따라서, 국내 자체처분 폐기물(원자력안전위원회 고시 2017-65호에 따른 자체처분 허용농도 또는 자체처분 허용선량을 만족하는 폐기물)에 대한 현행 규제체계가 대량의 콘크리트 폐기물에 대한 무제한적 자체처분에 대해서도 유효성을 유지할 수 있는지를 사전에 확인할 필요가 있다. 이와 관련, 국내 자체처분 규정 개발 시 참조기준인 IAEA SRS No. 44를 심층분석하고, 국내 산업계 현황을 반영한 입력값과 계산식을 이용하여 4가지 자체처분 시나리오에 대한 예상 피폭방사선량을 평가하였다. 그 결과, 재활용 시나리오에 대한 예상선량은 대부분 정상 시나리오에 대한 자체처분 선량 기준(즉, $0.01mSv{\cdot}y^{-1}$)보다 낮은 것으로 평가되었으나, 성토 후 거주 시나리오의 경우 보수적인 가정을 적용하면 자체처분 선량 기준을 초과할 가능성도 배제할 수 없는 것으로 나타났다. 따라서, 대량의 해체 콘크리트 폐기물의 안전하고 지속가능한 자체처분을 위해서는 폐기물 처리업체 다변화, 성토 시나리오에 대한 보다 구체적인 평가, 성토를 통한 자체처분에 대한 부분적 제한조건 설정 등을 고려할 수 있다.