• 콘크리트학회논문집
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• 제12권3호
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• pp.39-46
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• 2000

This study is to investigate the watertightness properties of waterproofing admixture mixed redispersible polymer and siliceous powder. Series I deals with change in micro-structure of mortar by waterproofing admixture according to the water/cement ratios of 0.5, 0.6, 0.7 and 0.8 Crystal growth in micro-structure was observed through SEM to estimate on the watertightness effect of it. SeriesII deals with watertightness properties of waterproofing admixture on water permeability coefficient, crack restoration capacity and carbonation depth. SeriesII deals with watertightness properties of waterproofing admixture on water permeability coefficient, crack restoration capacity and carbonation depth. The result of this study can be summarized as follows. 1) Fluidity of mortar and concrete was increased by adding waterproofing admixture. 2) From observation through SEM. Crystals grew larger and denser in micro-structure as fiberic crystalization. 3) Waterproofing admixture is good watertightness properties in a level of high water/cement ratios and long limit of time. 4) Crack restoration capacity was appeared and durability was progressed by waterproofing admixture.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2006년도 춘계 학술발표회 논문집(II)
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• pp.617-620
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• 2006

This study is related to comprehending performance for watertightness and crack control of concrete added with crack reducing agent concerning to high strength concrete mixs. It was confirmed that watertightness of concrete added with agent could be improved by evaluation absorption ratio, permeability ratio and pore size distribution of hardened concrete. As well resistance to crack resulted from shrinkage was transferred to better state by the addition of agent.

• 한국농공학회논문집
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• 제49권1호
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• pp.45-54
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• 2007

This study was performed to evaluate strength and watertightness properties of EVA modified high strength concrete in order to improve durability of concrete used in agricultural water utilization facilities that are in constant contact with water. Materials used were cement, coarse and fine aggregates, silica fume, EVA and AE water reducing agent. Tests for the slump, compressive and flexural strengths, absorption ratio and permeability coefficient according to curing condition (water and water+dry curing) and content ratio of EVA were performed. The slump results of EVA modified high strength concrete similarly showed in the content ratio of EVA powder less than 4% and decreased in the content ratio of EVA powder more than 6% compared to that of concrete without EVA powder. The compressive strength of EVA modified high strength concrete decreased with increasing the content ratio of EVA powder. The flexural strength of EVA modified high strength concrete increased with increasing the content ratio of EVA powder in the content ratio of EVA powder ratio less than 4% and had similar or slightly decreased in the content ratio of EVA powder more than 6% compared to that of concrete without EVA powder. The absorption ratio and permeability coefficient of EVA modified high strength concrete decreased with increasing the content ratio of EVA powder in the content ratio of EVA powder less than 4% and slightly increased in the content ratio of EVA powder more than 6%.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2005년도 추계 학술발표회 제17권2호
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• pp.719-722
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• 2005

The watertightness of concrete is judged by the depth of penetration of water forced in under pressure with the mechanism of flow of seepage water examined theoretically and experimentally. As a result, it is found that in the case of low water pressure approximately 0.15Mpa or less, the flow is Darcy seepage flow, the same as flow in an ordinary sand stratum, whereas in the case of high water pressure, the flow is diffused seepage flow accompanied by internal deformation of concrete. It is suggested that the watertightness of concrete be evaluated by seepage coefficient in the case of the former and diffusion coefficient in the case of the latter.

• 한국건축시공학회지
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• 제21권6호
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• pp.593-604
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• 2021

본 연구에서는 콘크리트 구조물 외벽에서 발생하는 균열 대응 및 수밀성 향상 목적으로 특수하게 개발된 탄성 방수성 도료와 일반 수성 페인트를 대상으로 비교시험을 진행하였으며, 이를 통해 탄성 방수성 도료의 성능 향상 정도를 확인하였다. 비교실험 결과, 균열 차폐성 확보를 통해 수밀성 향상이 가능한 것으로 확인하였으며, 일반 수성 페인트 대비 약 10배 이상의 균열 대응성을 확보한 것으로 확인하였다. 또한, 최소 1.3MPa의 부착성능 및 0.1MPa의 투수압에도 저항이 가능한 것으로 확인하여 방수적 측면에서 안정성을 확보한 것으로 확인하였다.

• 콘크리트학회지
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• 제3권3호
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• pp.101-110
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• 1991

이 연구는 피치계 탄소섬유 보강 플라이애쉬.시멘트 복합체의 여러 가지 특성을 실험적으로 구명하고, 그 제조방법을 제시한 것이다. 복합체는 조강시멘트, 시리카 분말, 스티렌 부타디엔 러버 라텍스, 기포제와 탄소섬유 및 플라이애쉬를 사용하여 제조하였고, 배합조건별로 그 특성을 검토하였다. 연구결과, 경량 탄소섬유 보강 플라이애쉬.시멘트 복합체의 압축강도, 인장강도, 휨강도, 흡수성 및 특수성 그리고 건조수축과 같은 물리적.역학적 성질은 스티렌 부타디엔 러버 라텍스를 첨가하므로써 현저히 개선되었으며, 아울러 복합체를 제조하는데는 기건양생보다 오토클래브 양생이 유리한 것으로 나타났다. 이결과, 앞으로 경량 탄소섬유 보강 플라이애쉬.시멘트 복합체를 이용한 프리캐스트 제품의 개발에 크게 기여할 수 있을 것으로 기대된다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2003년도 춘계학술대회 논문집 기술교육전문연구회
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• pp.149-153
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• 2003

In URD(Underground Residential Distribution) power cable, experiments of WVT(Water Vapor Transmission) test on the Base Resin accomplished to specimens which contained CB(Carbon Black), anti-oxidant to base resin and made by pressing to resin of pellet or lump form. a kind of specimens was HDPE(High Density Polyethylene), MDPE(Medium Density Polyethylene), LDPE(Low Density Polyethylene), LLDPE(Linear Low Density Polyethylene), PVC(Polyvinyl Chloride). as a results of WVT test, we saw that WVT ratio was HDPE < LLDPE < MDPE≒LDPE${\ll}$ PVC. WVT properties of PVC using for jacket showed properties 15-20 times more than MDPE or LLDPE. Therefore, to development of watertightness cable, our works present need of Changing in insulating materials.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2001년도 추계학술대회 논문집
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• pp.52-56
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• 2001

Experiments of 2 type on insulating compounds accomplished to change PVC using in URD(Underground) power cable jacketing. one was DB(Dielectric Breakdown) test on the pure base resins and the others were WVT(Water Vapor Transmission) test on the compounds which contained C/B(Carbon Black), anti-oxidant to base resin. a kind of specimens made by pressing to resin of pellet or lump form was HDPE(High Density Polyethylene), MDPE(Medium Density Polyehylene), LDPE(Low Density Polyethylene), LLDPE(Linear Low Density Polyethylene), PVC(Polyvinyl Chloride). As a results of AC DB and WVT test, we saw that strength of Insulation was HDPE> LLDPE = MDP E> LDPE and WVT ratio was HDPE

• 산업기술연구
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• 제33권A호
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• pp.101-107
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• 2013

The purpose of this study was to investigate bond strength between substrate and HES-LMS mortar, durability of HES-LMS mortar with latex content(0%, 5%, 10%). To measure the bond strength, the direct tensile test based on uniaxial tensile test was used, which was proposed by Kuhlman(1990). Also, Resistance for water permeability, water absorption and image analysis for air void system were conducted to estimating durability of HES-LMS mortar.

• 한국농공학회지
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• 제41권1호
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• pp.97-105
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• 1999

Recently , polymer concrete has been widely used in the construction industry because of its quick setting, high strength, excellect adhesion, watertightness and chemical resistance compared to ordinary cement concrete. Its application is also increased. In this paper, lightweight polymer mortars using unsaturated polyester resin and lightweight aggregate are prepared with various mix proportations, and tested for slump working life, apparent specific gravity , flexural and compressive strengths. As a result, the slump and working life can be controlled and thier flexural and compressive strengths are 9.7 to 22.0 MPa , and 23.0 to 100.8 MPa respectively at apparent specific gravities of 0.86 to 1.73.