• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2016년도 춘계 학술논문 발표대회
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• pp.126-127
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• 2016

In this research, the optimum combination of fly ash (FA) and blast furnace slag (BS) was deduced by analyzing the performance of high volume supplementary cementitious materials (SCMs) cement mortar depending on various combinations of cement, FA, and BS. As a result, increased workability was shown with increased the portion of FA, while air content, setting time, and compressive strength were decreased.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2016년도 춘계 학술논문 발표대회
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• pp.91-92
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• 2016

Structural integrity of reinforced concrete structures including nuclear power plants needs to be evaluated on a regular basis. Deterioration inside the concrete structures can be represented by voids. In this study, the varied volume fraction of voids inside mortar specimens was studied as a parameter using ultrasonic testing equipments. Both direct and indirect measurement methods were employed. The results show that there is a clear distinction between the specimens with different void volume fractions.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2015년도 춘계 학술논문 발표대회
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• pp.44-45
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• 2015

Although the carbonation problem of high-volume slag concrete has been solved by the mixed use of emulsified refine cooling oil as the pilot study, there was an instance of securing air quantity and frost resistance followed by the use of Expancel due to the problem of having vulnerability in frost resistance in result as the air quantity has not been secured. But due to the problem of Expancel not being economical, air quantity and frost resistance of high-volume slag concrete mixed with ERCO are attempted to be secured using micro bubble that can remain in the water for a long time as a relatively economical and very microscopic bubble.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2015년도 춘계 학술논문 발표대회
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• pp.23-24
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• 2015

As this study is an experiment for solving problem on the carbonation acceleration of high volume admixture concrete, the capillary pore getting filled up by saponification as cooking oil gets absorbed to the concrete surface in case of applying a cooking oil based coating agent to the concrete has been verified in the previous studies. Accordingly, this study has performed a comparative experiment on the cooking oil and the anticorrosive coating agent sold on the market while the result followed by this experiment has shown the fact of indicating similar carbonation penetration depth and porosity.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2014년도 추계 학술논문 발표대회
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• pp.133-134
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• 2014

As a previous research, improved durability of concrete by filling capillary pores with waste cooking oil was suggested as a method of controlling carbonation of the concrete replaced high volume of SCMs. on the other hand, the emulsified refined waste cooking oil for better mixing performance had a drawback of reducing air content related with decreasing freeze-thawing resistance. As a solution of this problem, surface applying method was suggested instead of adding in mixing process, and in this research, the performance regarding concrete durability are evaluated comparing emulsified refined cooking oil with water-repelling agent.

• Wind and Structures
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• 제14권1호
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• pp.71-80
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• 2011

This study presents a decision making process for installation of wind barrier which is used to reduce the wind speed applied to running vehicles on expressway. To determine whether it is needed to install wind barrier or not, cost and benefit from wind barrier are calculated during lifetime. In obtaining car accidental risk, probabilistic distribution of wind speed, daily traffic volume, mixture ratio in the volume, and duration time for wind speed range are considered. It is recommended to install wind barrier if benefit from the barrier installation exceed construction cost. In the numerical examples, case studies were shown for risk and benefit calculation and main risky regions on Korean highway were all evaluated to identify the number of installation sites.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2017년도 추계 학술논문 발표대회
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• pp.81-82
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• 2017

This study analyzed the compressive and flexural strength characteristics and the permeability coefficient of the trial product of amorphous metallic fiber reinforced porous block using high volume blast furnace slag powder.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2013년도 춘계 학술논문 발표대회
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• pp.318-320
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• 2013

The spherical bead manufactured by rapidly cooling process shows high density of 3.64g/㎤, high unit volume weight of 2.6kg/l, and high solid volume of 71%. When it applies to the grouter, it is possible to obtain even high fluidity with only a small amount. This study, focusing the grouter using a rapidly-cooled electric arc furnace oxidizing slag(RC-EAFS), deals with the properties of flow and setting time in fresh state, compressive strength and length variation at 1, 3, 7 and 28 curing day in hardened state. As the results, even though the grouter with RC-EAFS shows comparative low strength, it will be possible to development the competitive product due to the properties of increasing flow and low cost.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2001년도 학술논문발표회
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• pp.82-87
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• 2001

The purpose of this study is for the active use of the fly ash, which is a by-product of the combustion pulverizes coal thermal power plants, to compensate for the lack of landfill and for conservation of energy, by using fly ash as the supplementary cementitious material, and to prove its possibility as the related products of the cement. First of all, the ordinary fly ash is grinded in a special method and its fineness is controlled from 6000$\textrm{cm}^2$/g to 8000$\textrm{cm}^2$/g, then replaced it with the 10% to 80% of the cement mortar in order to test physics characteristics. The first experiment conducts on the strength development in fly ash replacing content and fineness. and the changes of the flow values, incorporating fly ash into cement. The second one is about the slow development of the strength of the fly ash mortar in early ages, and improves its strength with the activator $Na_{2}SO_{4}$, using high volume fly ash.

• 한국건축시공학회지
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• 제9권3호
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• pp.73-78
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• 2009

Coal ash is a by-product of the combustion of pulverized coal, and much of this is dumped in landfills. The disposal of coal ash is one of the major issues for environmental problems. In this paper, the effects of the kinds and replacement ratio of coal ash on the durabilities of concrete mixtures are investigated. Fine aggregate was replaced with coal ash(fly ash and bottom ash) in five different ratios, of 0%, 10%, 20%, 35%, and 50% by volume. Test results indicated that the compressive strength increased with the increase in fly ash percentage. The loss of compressive strength of bottom ash concrete mixes after immersion in sulphuric acid solution was less than in the control mix(BA0). In addition, the carbonation depth of fly ash concrete mixes was lower than the control mix(FA0).