• Proceedings of the Korean Ceranic Society Conference
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• 2000.10a
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• pp.120.1-120
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• 2000

• Proceedings of the Korean Ceranic Society Conference
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• 2000.10a
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• pp.124.1-124
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• 2000

• Magazine of RCR
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• v.10 no.4
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• pp.57-64
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• 2015

• Clean Technology
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• v.19 no.3
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• pp.272-278
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• 2013

Ethylene propylene diene terpolymer (EPDM) has been usually used for various applications. Bottom ash generated in thermoelectric power plant is hardly recycled. In this study, EPDM/bottom ash/talc composites were prepared by using roll-mill. Bottom ashes obtained from thermoelectric power plant were modified using surfactant. The processing materials used in this study were antioxidant, processing oil, cross-linking co-agent and softening agent. Morphology and physical properties of EPDM composites are investigated by using SEM, TGA, UTM and Rheometer. As a result, when modified ash and talc are added to EPDM composites, the tensile strength and modulus of EPDM composites were remarkably enhanced.

• Journal of the Korean Geotechnical Society
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• v.17 no.2
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• pp.59-72
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• 2001

적황색토와 플라이애쉬의 혼합비율에 증가에 따라 건조밀도도 증가하며 최적함수비는 감소하는 경향이고 2차 첨가재인 소석회 및 시멘트 첨가에 의한 건조밀도의 증가는 보이나 처리토의 경량화의 범위는 1:03~1:0.5 정도임을 확인할 수 있었다. 프라이애쉬의 혼합비율이 증가해도 프라이애쉬의 고유산화칼슘(CaO)의 함유량이 적으면 유리산화칼슘의 증가도 크지 않으나, 2차 첨가재인 소석회 및 시멘트 첨가량의 증대에 따라 증가한다. 이는 첨가재에 의한 수화반응의 증가로 확인되며, 본 처리토는 Ion 교환작용과 Pozzolan 반응 생성물인 규산칼슘석회수화물(5CaO.6SiO$_2$.5$H_2O$, Tobermorite)과 알민산유산석회수화물(3CaO.Al$_2$O$_3$.3CaSO$_4$.32$H_2O$, Ettringite)가 주된 반응생성물이며 확인된 알민산유산석회수화물(Ettringite)의 회절 X-선 강도는 2차 첨가재의 첨가에 따른 수화반응으로 수화물은 점차 증가하며 상대적으로 일축압축강도도 상응한 강도발현을 하여 고결화 효과에 기여하고 있음을 보여준다.

• Journal of the Korea Institute of Building Construction
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• v.7 no.1 s.23
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• pp.91-98
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• 2007

In this study, the property and plastic cracking pattern of concrete were compared and analyzed with the replacement ratio of fly ash 0, 5, 10, 15, 20% by cement weight. And curing conditions of concrete were given variously such as indoors(with wind speed as 0, 300, 500m/min), outdoors and chamber. The hydration temperature had a tendency to decrease as the replacement ratio of fly ash increased, and in the case of the wind speed 0m/min, it was showed that the moment that the amount of evaporation of water from surface of reference concrete was more than the volume of bleeding was 90 min since casting concrete. The time that the crack initiated had a tendency to be more quickly as the replacement ratio of fly ash increased. The number, length, width and area of crack in the indoor curing, exposed outdoor curing, enclosed outdoor curing had a tendency to decrease as the replacement ratio of fly ash increased. The crack had a tendency to decrease in sequence of exposed outdoor, enclosed outdoor curing, indoors curing. The outbreak of cracking by the change of temperature and humidity was affected by relative humidity more than temperature and the cracking had a tendency to increase as relative humidity lowered.

• Journal of Ocean Engineering and Technology
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• v.19 no.6 s.67
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• pp.29-34
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• 2005

This paper describes the effect of fly ash replacement on seawater resistance of anti-washout underwater concrete, which was replaced cement by fly ash from $0\%$ to $50\%$. The experimental work was performed to find out the variations of length and weight of specimens, using a chloride acceleration test in $40\^{\circ}$C The results shaw that the admixture using fly ash on an anti-washcout underwater concrete in the sea environment makes it more durable for the attacks of chloride by seawater. Also, the length of specimens of anti-washout underwater concrete, at age 180 days, increased substantially, compared with normal concrete; however, the mixture in which cement was replaced $50\%$ of fly ash shows $93\%$ reduction of the expansion, compared with the normal anti "washout underwater concrete specimen.

• Journal of the Korea institute for structural maintenance and inspection
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• v.18 no.4
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• pp.84-91
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• 2014

In this study, in order to find the improvement effect of metakaolin for using improvement of strength in concrete structures, it is investigated the diffusion coefficient of chloride ions and adiabatic temperature rise test. As a result, due to the mixing of metakaolin, it has been confirmed reducing diffusion coefficient of chloride ions and could prevent down of slump for use of adding fly ash. Therefore, ensuring resistance to chloride ion penetration into concrete, it is possible to enlarge the W/B ratio and reduce the adiabatic temperature rise by mixing of metakaolin. So, it is confirmed that the durability of concrete structures is increased.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2007.11a
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• pp.67-70
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• 2007

In this study, the characteristic of strength development of high volume fly ash concrete(HVFAC) was experimentally investigated. The production of one ton of portland cement releases about 0.87ton of CO2 into the atmosphere. HVFAC is an emerging material technology and is environmentally friendly because of its reduced use of portland cement, reduced CO2 emissions. For this purpose, two levels of W/B were selected. Seven levels of fly ash replacement ratios and two levels of silica fume replacement ratios were adopted. In the concrete mix, the water content of 125kg/m3 was used, which is less than that of usual water content. As a result, it was observed that the slump of concrete was increased with the increasing fly ash replacement ratio and when the silica fume was incorporated into the concrete, the slump was significantly decreased at the same condition. It appeared that the compressive strength gradually decreased with increasing fly ash replacement ratio at the early age, but the difference of strength up to replacement ratio of 50% was little at the age of 91 days because of the pozzolanic reaction of fly ash.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2018.11a
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• pp.83-84
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• 2018

As the concentration of greenhouse gases in the atmosphere increases, the reduction of CO2 is gaining worldwide attention. In the construction industry, cement replacement materials such as fly ash and blast furnace slag were investigated to reduce CO2 emissions in cement production process. Precast concrete is used in the field after manufacturing in the factory in the form of pipes and bricks because of shortening construction period and cutting construction cost. According to the results of previous research, it is known that early CO2 curing in concrete using OPC or fly ash has an initial strength enhancement effect and can be used for precast concrete production. Therefore, the purpose of this study is to evaluate the strength improvement effect by confirming the initial strength improvement effect when blast furnace slag is mixed.