• Proceedings of the Korea Concrete Institute Conference
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• 2008.11a
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• pp.429-432
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• 2008

Cathodic Protection Method was introduced as a corrosion protection method of metals under the ground or sea. Since 1970, it was applied to corrosion protection method of reinforced concrete structures. After 1990, this method has been used around the world, and its usability was proved. But this method has some problems on the aspect of construction and economy. In order to solve these problems, Cathodic Protection Method by using high durable metal spray was developed. First, the specimen was covered with anodic materials (Zn, Al) by using metal spray. And a performance of corrosion protection was confirmed by measuring corrosion current of specimen. Through the result of experiment, it is possible to know that Cathodic Protection Method by using high metal spray is good to protect to corrosion on reinforced concrete structures.

• Magazine of the Korea Concrete Institute
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• v.10 no.3
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• pp.209-218
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• 1998

본 연구에서는 콘크리트내 철근의 방식성을 검토하기 위하여 실제 구조물과 유사하도록 콘크리트 대형 패널 실험체를 제작하였으며, 실험체 제작시 콘크리트 내부에 염화물을 혼입하여 음극전기방식 공법을 도입한 실험체와 공법을 도입하지 않은 실험체의 염화물에 의한 철근방식효과를 비교 분석하였다. 실험에 사용된 음극전기방식은 비소모성 티타늄 양극망을 사용한 외부전원방식이며, 최근에 국내에서도 사용실적이 늘고 있는 리모트 모니터링 시스템을 적용하여 구조물의 유지관리상 연속성 있게 콘크리트내 철근의 방식정도를 확인할 수 있는지에 대해 검토하였다.

• Journal of the Korean GEO-environmental Society
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• v.14 no.6
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• pp.5-11
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• 2013

Because the regulation for a noise and a vibration in our country has been being reinforced more and more, a more environment-friendly pile construction method than a current low-noise and low-vibration method was needed for the close construction in the downtown area. In this study, the characteristics of a screw concrete pile method for noise and vibration-free method was explained, and it's vertical bearing capacity was studied in the base of the static pile load test data of the screw concrete piles. Constructed by two methody; a pre-digging shoe type construction method and a toe-jetting shoe type construction method. The vertical load bearing capacity of a screw pile constructed by the former was more about 70% than that of a screw pile constructed by the latter.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2013.10a
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• pp.247-249
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• 2013

열화한 철근콘크리트 구조물에 대하여 성능회복을 위하여 전기화학적 방식, 단면복구공법, 균열보수공법, 표면마감공법 등이 상용되고 있다. 본 연구에서는 단면복구공법의 적용과 성능예측을 위한 해석 모델의 입력값으로 사용될 보강철근과 단면복구재의 부착특성을 평가하기 위하여 철근인발실험을 실시하였다. 폴리머시멘트몰탈이 사용되었으며 부착요소의 강성과 강도를 구하여 비선형 해석을 실시하여 상당한 정확도의 예측값을 도출하였다.

• Proceedings of the Korea Concrete Institute Conference
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• 2009.05a
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• pp.399-400
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• 2009

This study arranged the result corrosion inhibition using Nano-silica for efficient prevention to diffusion of chloride ion. For the results, significant difference was not found on slump and air content, and there were superior effect to preventing diffusion of chloride ion on hardened concrete. It seemed to be Nano-silica prevented diffusion of chloride ion.

• Journal of the Korea institute for structural maintenance and inspection
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• v.13 no.3 s.55
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• pp.119-126
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• 2009

This study investigated the fire resistance of RC columns applying Fiber addition method, Fire board attaching method, and Fire proof sparying method. The results were summarized as following. The test showed that increase of fiber content, as expected, decreased the fluidity of fresh concrete, but for the types of fiber, the specimens containing nylon(NY) was favorable. The incline of fiber content also affected on the air content of concrete, which the specimens adding polypropylene(PP) fiber was the lowest, followed by a less decrease in polyvinyl alchhol(PVA) and then NY respectively. For the compressive strength at 28days, it was over 50MPa and showed slight increasing tendency by rising fiber contents. After the fire test completed, control concrete exhibited the severe demage, while the specimens containing more than 0.05vol.% of PP and NY was able to protect from spalling. In the case of splay, the partly spalling occurred at the all finishing material, however the RC columns were protected from spalling. For the methods attached with boards, all RC columns were protected except the dry attaching method. The reduced weight ratio was favorable because it was below 8 % except for plain concrete.

• Journal of Korean Tunnelling and Underground Space Association
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• v.16 no.4
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• pp.347-360
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• 2014

Recently construction of large sewer tunnels used also as underground sluiceways/storages is increasing in order to prevent urban inundation, untreated sewage flow into rivers from combined sewer overflows and consequential river pollution due to climate change. Most of these large sewer tunnels are constructed with concrete and the concrete lining should be protected from corrosion caused by hydrogen sulfide($H_2S$). This paper introduced popular concrete corrosion protection methods for large sewer tunnels with 100-plus years of life cycle, and pros and cons of each corrosion protection methods were described by giving specific examples. However, it is difficult to objectively assess corrosion protection alternatives because of insufficient track record of corrosion protection methods applied to large sewer tunnels. In this paper, the evaluation process for selecting a corrosion protection alternative was introduced for large sewer tunnels using a case study.

• Proceedings of the Korea Concrete Institute Conference
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• 2008.04a
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• pp.705-708
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• 2008

To obtain tunnel concrete safety in case of fire, this study analyzed fire proof characteristics by fire proof method change, and the results are as follows. As a fire proof characteristics by RABT temperature heating curve, plain concrete experienced severe spalling by initial extremely high temperature. In view of fire proof method, in the cases of organic fiber mixing method and board method, spalling was prevented, and in the case of spray method, severe spalling of over 100mm depth occurred along with exposure of structural concrete including spray coat by heat stress, etc while metal lath, the stiffener, falls off. As for fire proof characteristics by RWS temperature heating curve, in case of organic fiber inclusion, concrete surface experienced fusion of within 5mm, while in the case of spray method, spray coat was severely spalled to a depth of over 100mm causing structural body concrete to expose its reinforcement, and also in the case of board method, board was fused by high temperature, causing structural body concrete be directly exposed to high temperature, which triggered overall fall-off phenomenon, so in such extraordinary high temperature heating condition, establishment of special fire proof measures is needed.

• Journal of the Korea Concrete Institute
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• v.17 no.1 s.85
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• pp.3-10
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• 2005

The purpose of this study is to investigate the properties of composite systems using polymer cement and epoxy resins for waterproofing and anti-corrosion to concrete structures such as water supply facilities and sewage-works. For the waterproofing and anti-corrosion of concrete structures, there can be required various properties such as absorption capacity and water permeability, adhesion and tensile strength, hair crack-resistance, impact-resistance, repeated low and high temperature test and chemical resistance, soundness for drinking water, soundness for drinking water and etc. In this study these engineering properties of composite systems using polymer-modified mortar and epoxy resins were examined and could be confirmed to satisfy the guidelines of KS. Especially, it was turn out that the adhesion properties was excellent and high crack-resistance up to 1.49 mm will be perform.

• Proceedings of the Korean Institute of Industrial Safety Conference
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• 1999.06a
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• pp.187-191
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• 1999

공사현장에서 사용하고있는 거푸집의 대체를 오랫동안 연구 끝에 가로(60cm) 세로(120cm)의 규격의 PE-FORM을 개발한바 있으나, 일반 건설 현장에서 어떠한 형태의 구조물 시공을 위한 형틀을 제작함에 있어 통상적으로 기존 합판거푸집을 사용하고 있으나, 현재 국내에서 사용되고 있는 합판은 전량 수입에 의존하고 있어 외화낭비가 심할 뿐 아니라 평균 2-3회 정도밖에 사용하지 못해 자원 낭비를 초래하고 있으며, 합판 거푸집을 사용한 경우, 목공이 구조물의 형태에 맞춰 FORM을 일일이 제작해야하므로 시간과 비용의 소모가 크고 또한 FRP-FORM, EURO-FORM, STEEL-FORM GANG-FORM SYSTEM-FORM 등 구조물의 성격 형태에 따라 각종 개량된 거푸집을 사용한다고 해도 그것은 단순한 구조물의 형상을 만들어 내기 위한 형틀로써만이 이용되고 있을 뿐, 그 이상의 목적으로는 활용 할 수 없기 때문에 구조물의 특성상 방수 방식의 기능이 요구될 경우, 거푸집 해체 후 벽체의 내부 또는 외부에 액체, 몰탈, 에폭시, 쉬트 방수등 별도의 후속 공정이 추가되 번거로움이 있는 반면, 그 효과는 기대에 크게 미치지 못하고 있는 점을 착안, 수년 전부터 연구에 착수, 콘크리트 구조체의 방수ㆍ방식 문제를 해결 할 수 있는 획기적인 공법의 PE-PANEL의 요철형 거푸집 및 방수ㆍ방식공법을 개발해내는데 성공함으로써 지금까지 난제로만 여겨졌던 목재 거푸집의 대체 자재개발과 아울러 거푸집 겸 콘크리트 표면의 마감 처리을 동시에 해결한 매우 혁신적인 신기술이라 할 수 있다. (중략)