• Proceedings of the Korea Concrete Institute Conference
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• 2004.05a
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• pp.664-667
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• 2004

It may have to establish the definite standard for performance evaluation basis about cementitious waterproofing material in job site that applied the method of construction formed cement waterproof course on concrete surface In present paper shows the effective selection method of waterproof layer of optimum thickness for economic performance as evaluating of the need thickness on waterproof property of penetrating waterproofing material.

• Proceedings of the Korea Concrete Institute Conference
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• 2009.05a
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• pp.471-472
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• 2009

Recently, UH-PH SC (Ultra High PH Strength Concrete) used in High rise building is the material increases in tendency. Thus, the results indicate that it is possible to fireproof panels, fire protection of materials.

• Proceedings of the Korea Concrete Institute Conference
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• 1996.10a
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• pp.175-182
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• 1996

This paper deals with the properties of water permeability and porosity of cement mortar substrate coated with siliceous slurry coating under the exposure environment. Conditions of exposure enviornment are four kinds of in constant temperature water and humidity box, in indoor and outdoor exposure. Coated mortar substrate was expected continually increase in water and humidity condition, but was not in dry condition. Watertightness effect of siliceous coating was better in the condition of humidity then the dry condition, and the pore volume was decreased in that condition.

• Cement
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• s.193
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• pp.16-23
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• 2012

기후변화 및 환경보호에 대한 관심이 커지면서 각국은 에너지절약, 탄소배출량 감축 및 환경보호 등을 명분으로 기술규제 도입을 확대하고 있다. 2011년도 전 세계 TBT(무역기술규제) 통보문 수가 1,101건에 달하는 가운데 에너지 환경 관련 기술 규제는 2004년 99건에서 2011년 200건으로 2배 이상 급증했다. WTO에 제출된 TBT 중 개도국 비중이 2004년 51.6%에서 2011년 81.2%까지 상승할 정도로 그 비중이 크게 높아졌다. 여기서는 에너지 및 환경 관련 전세계 규제동향을 조사하고 특히 올해 새롭게 시행 적용되는 각국별 환경 규제와 그 영향을 분석하여 우리 기업의 대응방안을 모색해 본다.

• Journal of the Korean Ceramic Society
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• v.40 no.12
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• pp.1229-1234
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• 2003

The utilization of metakaoline as a mineral admixture for cement has received considerable attention in recent years. This paper investigates the rheological properties of cement pastes containing metakaoline in view of fluidity. The rheology of the paste is assessed by using a BROOKFIELD RVDV II + viscometer (SC4-21, 29) having cylindrical spindle. The results show the fluidity of cement pastes with metakaoline is increased by increasing W/S ratio and the dosage of superplastcizer. And also cement pastes with metakaoline as a partial replacement of cement show a dilatant behavior. Dilatancy is heavily influenced by W/S ratio and by the amount of metakaoline. However the thixotropy of the pastes is increased by silica fume.

• Journal of the Korean Ceramic Society
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• v.40 no.12
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• pp.1235-1240
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• 2003

The mixtures which are in the chemical composition of Portland cement were prepared from oyster shell, casting dust and BOF slag. The clinkerbility and the behaviour of formation of clinker minora]s were studied using the mixtures mainly by the mineral and microstructural observation. By virtue of the characteristics of starting raw materials, the clinkering temperature was lower as much as 100$^{\circ}C$ than that of a mixture prepared from normal raw materials. Uncombined calcium oxide was vanished entirely below 1350$^{\circ}C$. and the formation of major cement minerals such as alite and belite could be nearly accomplished without too much liquid phase within 1400$^{\circ}C$.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.12 no.3
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• pp.81-90
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• 1992

This study gives results of 1aboratory investigations to minimize the slump loss of concrete using high range water reducing admixture (HRWR). Various factors influencing on the slump loss such as cement type, HRWR type and dosage time are investigated. The acquired results indicated that 30 minutes delayed dosage of HRWR is very effective on reducing the slump loss though this tendency makes a difference to some extent according to cement and HRWR type. For the most part, the more usage of HRWR increases, the higher the slump loss occurs and concrete using ordinary portland cement has the highest slump loss and concrete using fly ash 20% replacement cement with HRWR of naphthalene type has the good effect on reducing the slump loss.

• Journal of the Korean GEO-environmental Society
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• v.11 no.12
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• pp.37-45
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• 2010

The particle size of microfine cement(MC) is so small that it can be injected into silt layer. But the more particle size is miniaturized, the more the cohesion increases. This phenomenon results in the decrease of the perviousness of MC. In this study, the grouting effects of microfine cement with superplasticizer to maintain cohesion low and that of normal cement were investigated in rock. To estimate the grouting effects, TCR/RQD test for rock quality, lugeon test, borehole loading test for coefficients of elastic and deformative stress, borehole shear test for shear stress, detection p~q~t(pressure~flow~time) chart tests were carried out. The results using MC show a better permeability, modulus of elasticity, deformation, charge per unit, and recover efficiency of grouting material than those of ordinary portland cement except shear stress.

• Proceedings of the Korea Concrete Institute Conference
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• 2009.05a
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• pp.343-344
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• 2009

Compressive strength and chloride ions permeability measurements of ternary blended cement concretes incorporating ground granulated blast-furnace slag and fly ash were performed From a result of this study, it was found that there may be not a linear relationship between compressive strength and durability of ternary blended cement concretes.

• Proceedings of the Korea Concrete Institute Conference
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• 2010.05a
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• pp.323-324
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• 2010

The purpose of this study was to investigate alkali-silica reaction of accelerating agents in shotcrete. The test was performed with accelerating agents (aluminate, alkali-free, cement based mineral admixture) in the Type I cement. As a test result, using the nonreactive aggregates, detrimental expansion due to alkali-silica reaction doesn't occurred regardless of equivalent alkali contents of accelerating agent.