• 한국지반공학회논문집
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• 제23권11호
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• pp.77-85
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• 2007

본 연구에서는 준설토 및 Bottom ash를 동시에 재활용하기 위하여 개발된 복합지반재료의 역학적 특성을 고찰하였다. 본 실험에서 제작된 복합지반재료는 부산 신항 건설현장에서 채취한 준설토, 시멘트, 기포 및 삼천포 화력발전소에 서 발생한 Bottom ash로 구성되어졌다. 다양한 배합비로 제작된 복합지반재료의 역학적 특성을 고찰하고, 특히 Bottom ash 혼합에 의한 역학적 거동 특성을 조사하기 위하여 다양한 실내실험이 수행되어졌다. 복합지반재료에 대한 실험결과 응력-변형 관계와 일축압축강도는 배합조건에 크게 의존하는 것으로 나타났고, 특히 Bottom ash 혼합시 압축강도 및 응력-변형 곡선의 기울기가 증가하는 Bottom ash 보강효과를 확인하였다. 복합지반재료의 압축강도는 양생기간이 증가할수록 증가하며, 28일 강도는 7일 강도의 약 $1.7{\sim}1.8$배 증가하는 것으로 나타났다. 복합지반재료의 단위중량은 기포함량에 크게 의존하였다. 복합지반재료의 변형계수($E_{50}$)은 Bottom ash의 혼합으로 인해 강도가 증가함에 따라 증가되었다.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2002년도 가을 학술발표회 논문집
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• pp.39-42
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• 2002

Cloride attack of concrete is one of the important causes of corrosion of reinforcing steel in concrete with carbonation and frost damage. In this paper, the effect of fly-ash on the cloride attack were investigated by varying water binder ratio and fly-ash contents according to the chloride ion penetrationa test. (ASTM C 1202-94) The principal conclusions from this research were as follows: 1) The compressive strength of concrete at large ages, depends more on $C_2$S contents of base cement than fly-ash contents. 2) On the other hand, the chloride ion penetration of concrete at large ages, principally depends on fly-ash contents and the influence of type of base cement is insignificant.

• 산업기술연구
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• 제21권B호
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• pp.45-49
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• 2001

Many cities and provinces are rapidly depleting landfill spaces. As the result, some municities have adopted to incinerate their municipal solid waste(MSW). The motive behind the choice is that incineration significantly reduces the volume of solid waste in need of disposal, destroys the harmful organic compounds that are present in MSW, and provides an attractive source of alternative energy. Conclusively, the generation of MSW ash is expected to increse in the furture. However, disposing the MSW ash in landfills may not always be an environmentally or an economically feasible solution. This paper addresses the various issues associated with MSW ash and its possible use in construction applications.

• 한국환경과학회지
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• 제13권2호
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• pp.143-148
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• 2004

In this paper, the properties of inter - locking block using fly ash are discussed in order to provide economical advantages and improve quality, and protect environment and recycle resources. Fly ash is the by-product of coal in thermal power plant. The experimental parameters are fly ash content, the amount of AE water - reducing agent and mixing proportion of cement mortar. According to the experimental results, the improvement of quality in the side of strength, absorption ratio and freeze - thaw resistance for manufacturing inter -locking block and the curtailment of cost can be achieved in case of 15% of fly ash and 0.3% of AE water- reducing agent are mixed into mortar mixture of 1 :6(C:S).

• 한국해양공학회지
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• 제15권4호
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• pp.120-125
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• 2001

This paper describes the effect of fly ash replacement on the setting time of antiwashout underwater concrete, where cement was replaced by 0% to 50%. Experimental work was performed on the condition of sea water and in air to find out the characteristics of setting time between the concretes that were cast in air and cast in 15$^{\circ}C$ of sea water. The experimental results show that the setting time of underwater concrete with 50% replacement was delayed about 10 hours than normal concrete. And it can be concluded that, at the case of underseawater concrete addicted with fly ash, the delayed final setting times are shown as the function Tf=0.069F+7.69, where Tf is the delayed final setting time and F is quantity of fly ash, respectively. These results confirm that the setting time underseawater concrete could be prolonged.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2010년도 춘계 학술발표회
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• pp.489-494
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• 2010

A geo-composite soil (GCS) is a stabilized mixture of bottom ash, cement and dredged soil. Various samples with different mass ratios of mixtures were tested under curing time of 7 and 28 days to investigate physical properties and compressive strength. This paper focused on the effect of bottom ash on the strength characteristics of Busan marine dredged soil. Cement has been added as an additive constituent to enhance self-hardening of the blended mixture. The unconfined compressive strength of GCS increases with an increase in curing time due to pozzolanic reaction of the bottom ash. The strength after 28 days of curing is found to be approximately 1.3 to 2.0 times the strength after 7 days of curing, regardless of mixture conditions. The secant modulus of GCS is in the range of 55 to 134 times the unconfined compressive strength. The correlation of unconfined compressive strength with bottom ash content and initial void ratio are suggested.

• Computers and Concrete
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• 제5권5호
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• pp.449-459
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• 2008

This paper focuses on the application of two dimensional orthogonal polynomials in the regression analysis for the relationship of product parameters viz. compressive strength, bulk density and water absorption of fly ash cement bricks with other process parameters such as percentages of fly ash, sand and cement. The method has been validated by linear and non-linear two parameter regression models. The use of two dimensional orthogonal system makes the analysis computationally efficient, simple and straight forward. Corresponding co-efficient of determination and F-test are also reported to show the efficacy and reliability of the relationships. By applying the evolved relationships, the product parameters of fly ash cement bricks may be approximated for the use in construction sectors.

• 대한가정학회지
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• 제42권4호
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• pp.119-125
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• 2004

In this paper, the effect of the volcanic ash dyed on cotton knitted fabrics was studied in various ways. A cationic agent was used to improve the depth of color of the fabric in the dyeing process. K/S values of dyed fabrics were measured to examine the dyeing properties. Cationic agent pretreatment, followed by dyeing with volcanic ash, was tested. In the dyeing experiment, the effects of a wide range of parameters such as the concentration of cationic agent, treatment time, treatment temperature and treatment pH of the dyebath were studied. Experimental results showed that the pretreatment with cationic agent improved the dyeing properties of cotton knitted fabrics with volcanic ash. At this point, concentration of cationic agent was 4%(on weight of fabric), treatment time was 40minutes, treatment temperature was 80 C and treatment pH of the dyebath was a neutral condition.

• 한국해양공학회지
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• 제14권4호
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• pp.30-34
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• 2000

The concretes cast in the sea water would be likely to be rich mix and mass concrete. Therefore it is important to check out the hydration heat of concrete and to reduce it to prevent the concrete from processing the temperature crack. Recently the antiwashout agent is used on underwater concrete for preventing from the segregation of concrete in the water. The experimental studies were done for the combined cement replaced by fly ash 30%unit weight of binder to study on the characteristics of hydration heat of antiwashout underwater concrete, and its characteristic was discussed by comparing on cast in sea water with anther one in air. The present paper showed that the hydration heat concrete replaced by 30%of fly ash was more significantly reduced than the normal concrete. The hydration heat of antiwashout underwater concrete was highter than that of normal concrete, but it was reduced lower than the normal concrete by adding fly ash.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2004년도 추계 학술발표회 제16권2호
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• pp.321-324
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• 2004

The discharge of fly ash that is produced by coal-fired electric power plants is rapidly increasing in Korea. The utilization of fly ash in the raw materials would contribute to the elimination of an environmental problem and to the development of new high-performance materials. So it is needed to study the binder obtained by chemically activation of pozzolanic materials by means of a substitute for the exiting cement. This paper concentrated on the strength development according to the kind of chemical activators, the curing temperature, the heat curing time. Also Scanning electron microscopy and X-Ray diffraction analysis show what the reaction products of the alkali activated fly ash are.