• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2021년도 봄 학술논문 발표대회
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• pp.191-192
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• 2021

For the stable management of radioactive waste, it is necessary to secure a solidification treatment technology capable of immobilizing hazardous radioactive elements in a solid matrix. In this study, the feasibility of using recycled cement recovered from waste concrete as a solidifying material for radioactive waste was analyzed.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2014년도 추계 학술논문 발표대회
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• pp.156-157
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• 2014

Inorganic binding material was made by recycled resource and its applicability as pile-filling material was examined. The result was that the material had same liquidity with the liquidity of OPC and high reactivity with site soil. According to dynamic/static loading tests by site test-construction, the inorganic binding material met both design bearing capacity and settlement. Since the inorganic binding material showed same or better performance than OPC, the utilization possibility of the inorganic binding material made of recycled resource as pile-filling material was verified.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2013년도 추계 학술논문 발표대회
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• pp.8-10
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• 2013

Inorganic binding material was made by recycled resource and its applicability as pile-filling material was examined. The result was that the material had same liquidity with the liquidity of OPC and high reactivity with site soil. According to dynamic/static loading tests by site test-construction, the inorganic binding material met both design bearing capacity and settlement. Since the inorganic binding material showed same or better performance than OPC, the utilization possibility of the inorganic binding material made of recycled resource as pile-filling material was verified.

• 한국건설순환자원학회논문집
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• 제9권4호
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• pp.425-432
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• 2021

본 논문은 생활계 복합재질 폐플라스틱을 재활용한 물질재활용 제품의 물성을 향상시키기 위한 방안으로서 단일 재질 폐플라스틱인 r-LDPE(Recycled Low Density Polyethylene, r-LDPE) 사용량을 변화시켜 물질재활용 제품의 물성을 평가·분석하였다. 그 결과 r-LDPE 사용량이 증가할수록 생활계 복합재질 폐플라스틱 물질재활용 제품의 인장강도, 연신율은 증가하는 경향을 나타내었지만 회분은 감소하는 경향을 나타내었다. 생활계 복합재질 폐플라스틱 재생원료에 r-LDPE 사용량을 5% 이상 혼입 사용할 경우 생활계 복합재질 폐플라스틱의 물질재활용 제품인 인삼재배시설용 지주대의 품질기준인 GR M 3093-2021을 안정적으로 만족시키는 것으로 나타났다.

• 자원리싸이클링
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• 제30권1호
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• pp.53-59
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• 2021

생활계에서 발생되는 폐비닐은 토사, 금속, 유리 등의 이물질로 인해 고형연료(SRF, Solid Refuse Fuel)로 사용되었지만 최근 환경문제로 인해 고형연료의 사용량이 감소하고 있어 재활용이 필요한 실정이다. 본 연구에서는 폐비닐 재활용을 위해 우선 생활계 폐비닐로 생산된 복합 재생원료와 영농폐비닐로 생산된 PE 단일 재생원료에 대해 분석을 진행하였다. 원료 분석 결과, 폐비닐은 주로 폴리에틸렌으로 이루어져 있고 복합 재생원료는 약 2%의 회분이 잔존하고 있으며 PE 단일 재생원료의 경우는 회분이 없는 것을 확인하였다. 또한 두 재생원료의 배합비율에 따른 인장강도를 측정한 결과 열처리 온도 200 ℃, 압착 압력 30 MPa, 배합비율 3:7 (복합:PE 단일) 조건에서 인장강도가 최대 약 16 MPa임을 확인하였다. 굽힘강도는 열처리 온도 200 ℃, 압착 압력 30 MPa, 배합비율 3:7 (복합:PE 단일) 조건에서 최대 약 39 MPa임을 확인하였다. 따라서 재생원료들의 배합비율에 따른 강도 특성 변화를 확인함으로써 폐비닐의 재활용 가능성을 제시하고자 하였다.

• 한국재난정보학회 논문집
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• 제8권3호
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• pp.204-212
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• 2012

경량혼합토는 건설잔토나 준설토 및 현장에서 발생하는 점토나 실트질 흙을 사토처리 하지않고 현장에서 유용할 수 있는 매우 경제적이고 환경친화적인 재료이다. 최근에는 페자원(폐타이어가루, 왕겨)을 경량혼합토에 첨가하는 건설재료 재활용에 관한 연구가 진행 중에 있다. 본 연구에서는 경량혼합토를 제작하기 위해 필요한 배합설계변수인 원료토의 중량, 함수비 및 기포재와 첨가할 물의 양, 그리고 강도를 발현하기 위하여 필요한 고화재로서 시멘트첨가량에 대한 최적의 배합설계에 대한 분석을 하였다. 이를 위하여 일축압축시험에 의한 응력-변형 거동과 양생기간 및 성분비에 따른 강도분석, 폐기물 성분비에 대한 실험강도 비교분석을 수행하였다. 마지막으로, 합리적이고 경제적인 배합비 산출을 위하여 경량혼합토의 목표강도를 결정하고 최적의 배합설계 변수를 제시하였다.

• Computers and Concrete
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• 제21권3호
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• pp.321-333
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• 2018

Flat-slabs, being a significant structural component, not only reduce the dead load of the structure but also reduce the amount of concrete required for construction. Moreover the use of recycled aggregates lowers the impact of large scale construction to nearby ecosystems. Recycled aggregate based concrete being a quasi-brittle material shows enormous cracking during failure. Crack growth in flat-slabs is mostly in sliding mode (Mode II). Therefore sufficient sections need to be provided for resistance against such failure modes. The main objective of the paper is to numerically determine the ultimate load carrying capacity of two self-similar flat-slab specimens and validate the results experimentally for the natural aggregate as well as recycled aggregate based concrete. Punching shear experiments are carried out on circular flat-slab specimen on a rigid circular knife-edge support built out of both normal (NAC) and recycled aggregate concrete (RAC, with full replacement). Uniaxial compression and bending tests have been conducted on cubes, cylinders and prisms using both types of concrete (NAC and RAC) for its material characterization and use in the numerical scheme. The numerical simulations have been conducted in ABAQUS (a known finite element software package). Eight noded solid elements have been used to model the flat slab and material properties have been considered from experimental tests. The inbuilt Concrete Damaged Plasticity model of ABAQUS has been used to monitor crack propagation in the specimen during numerical simulations.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2010년도 추계학술대회 초록집
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• pp.199.1-199.1
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• 2010

Use of recycled aggregates that are constituents of concrete or asphalt-based structures has become popular because the recycling is an eco-friendly way to overcome the depletion of natural aggregates. In order to adopt the recycled aggregates for backfilling a power transmission pipeline trench, their thermal resistivity should be low enough to prevent thermal runaway in the transmission system. In this study, a series of laboratory tests with QTM-500 and KD2 Pro was performed to measure the thermal resistivity of recycled aggregates prepared from various sources. Relationships between the thermal resistivity of recycled aggregates and the water content have been obtained with consideration of compaction effort. Similar to natural soils, the thermal resistivity of the recycled aggregates decreases with increasing the water content. In addition, this study compared the experimental data with conventional prediction models for the thermal resistivity in the literature, which suggests the availability of the recycled aggregates as backfill material substituting for natural aggregates when backfilling the power transmission pipeline trench.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2005년도 춘계 학술기술논문발표대회 논문집
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• pp.61-64
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• 2005

Recently, there have been many studies about recycling cementitious powder from concrete waste(hereinafter referred to as waste powder), generated after recycle aggregate production. Previous studies showed that when the heating process of waste powder at $700^{\circ}C,\;Ca(OH)_2$ in paste is dehydrated making possible the restoration of hydraulic properties. Recycled cement with hydraulic properties restored is thought to be re-hydrated through the mechanism of hydration, which is almost similar in Portland cement. This clearly suggests that the hydrate of recycled cement is alkali in type. Like in general concrete, if recycled cement is used as a structural material, resistance performance against carbonation or neutralization by $CaCO_3$ in air probably would be most influential to the life of steel-reinforced concrete structure. Thus the purpose of this study is to make an experimental review on chemical properties of recycled cement, manufactured with concrete waste as base material, and investigate the durability of concrete using recycled cement through evaluating the cement s performance of resistance to carbonation in accordance with its accelerating age. Based on its results, further, the study seeks to provide basic information about ways of utilizing recycled cement.

• 한국건축시공학회지
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• 제6권4호
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• pp.61-68
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• 2006

Recently, there have been many studies about recycling cementitious powder from concrete waste(hereinafter referred to as waste powder), generated after recycle aggregate production. Previous studies showed that when the heating process of waste powder at $700^{\circ}C,\;Ca(OH)_2$ in paste is dehydrated making possible the restoration of hydraulic properties. Recycled cement with hydraulic properties restored is thought to be re-hydrated through the mechanism of hydration, which is almost similar in Portland cement. This clearly suggests that the hydrate of recycled cement is alkali in type. Like in general concrete, if recycled cement is used as a structural material, resistance performance against carbonation or neutralization by $CaCO_3$ in air probably would be most influential to the life of steel-reinforced concrete structure. Thus the purpose of this study is to make an experimental review on chemical properties of recycled cement, manufactured with concrete waste as base material, and investigate the durability of concrete using recycled cement through evaluating the cement's performance of resistance to carbonation in accordance with its accelerating age. Based on its results, further, the study seeks to provide basic information about ways of utilizing recycled cement.