아질산형 하이드로칼루마이트와 터폴리머 분말수지를 병용한 PCM의 강도 및 방청성

김완기,Kim, Wan-Ki 대한건축학회 2011 대한건축학회논문집 Vol.27 No.1

Nitrite type hydrocalumite is a material which can adsorb the chloride ions causing the corrosion of reinforcing bars and liberate the nitrite ions ($NO_2{^-}$) inhibiting the corrosion, and provides excellent corrosion-inhibiting property to the reinforcing bars in reinforced concrete by the addition of it to concrete. On the other hand, various redispersible polymer powders have been commercialized to manufacture the construction materials in the form of prepackaged-type products, which have rapidly been developed for lack of skilled workmen in construction sites. In recent years, terpolymer powders of improved quality have been developed and commercialized as cement modifiers. However, the properties of polymer-modified mortars using the terpolymer powders have not been studied till now. The purpose of the present paper is to examine the strengths and corrosion inhibition of polymer-modified mortars using a VA/E/MMA terpolymer powder with nitrite-type hydrocalumite (calumite) to develop the prepackaged-type materials for dry mortar. Polymer-modified mortars using a newly developed terpolymer powder as polymeric admixtures with the calumite are prepared with various calumite contents and polymer-binder ratios, and tested for strengths and corrosion inhibition. On the whole, the strength properties of VA/E/MMA terpolymer powder-modified mortars are considerably improved with an increase in the polymer-binder ratio regardless of the calumite content. and are remarkably improved over unmodified mortar. It is concluded from the test results that the replacement of the portland cement with the calumite causes a marked improvement in the corrosion-inhibiting property of the polymer-modified mortars.

폴리머 시멘트 슬러리 도장강의 개발 연구

김완기(Kim, Wan-Ki),조영국(Jo, Young-Kug),소승영(Soh, Seung-Young),소양섭(Soh, Yang-Seob) 한국콘크리트학회 2002 한국콘크리트학회 학술대회 논문집 Vol.2002 No.5

아질산형 하이드로칼루마이트와 터폴리머 분말수지를 병용한 PCM의 강도 및 방청성

김완기(Kim Wan-Ki) 대한건축학회 2011 大韓建築學會論文集 : 構造系 Vol.27 No.1

Nitrite type hydrocalumite is a material which can adsorb the chloride ions causing the corrosion of reinforcing bars and liberate the nitrite ions (NO₂?) inhibiting the corrosion, and provides excellent corrosion-inhibiting property to the reinforcing bars in reinforced concrete by the addition of it to concrete. On the other hand, various redispersible polymer powders have been commercialized to manufacture the construction materials in the form of prepackaged-type products, which have rapidly been developed for lack of skilled workmen in construction sites. In recent years, terpolymer powders of improved quality have been developed and commercialized as cement modifiers. However, the properties of polymer-modified mortars using the terpolymer powders have not been studied till now. The purpose of the present paper is to examine the strengths and corrosion inhibition of polymer-modified mortars using a VA/E/MMA terpolymer powder with nitrite-type hydrocalumite (calumite) to develop the prepackaged-type materials for dry mortar. Polymer-modified mortars using a newly developed terpolymer powder as polymeric admixtures with the calumite are prepared with various calumite contents and polymer-binder ratios, and tested for strengths and corrosion inhibition. On the whole, the strength properties of VA/E/MMA terpolymer powder-modified mortars are considerably improved with an increase in the polymer-binder ratio regardless of the calumite content. and are remarkably improved over unmodified mortar. It is concluded from the test results that the replacement of the portland cement with the calumite causes a marked improvement in the corrosion-inhibiting property of the polymer-modified mortars.

모바일 컨텍스트 Visualizer 설계

김완기(Wan Ki Kim),김문권(Moon Kwon Kim),천두완(Du Wan Cheun),배금주(Hyun Joo Bae),금창섭(Chang Sup Keum),김수동(Soo Dong Kim) 한국정보과학회 2011 한국정보과학회 학술발표논문집 Vol.38 No.1A

최근 스마트폰을 이용하여 위치, 움직임, 주위 환경 정보 등과 같은 사용자의 상황을 인지하고, 인지한 컨텍스트를 기반으로 어플리케이션 능동적으로 기능을 제공하기 위한 연구가 활발하다. 그러나 현재 컨텍스트 인지 모바일 어플케이션에서는 단일 사용자의 현재 컨텍스트에 국한되어 컨텍스트를 활용하고 있다. 본 논문에서는 제안하는 컨텍스트 Visualizer에서는 포괄적인 컨텍스트 정보의 활용을 위해 컨텍스트 정보를 개인, 그룹별로 분류하여 보여준다. 또한, 과거, 현재, 이래 컨텍스트 정보를 고려하여 화면에 보여줌으로써 컨텍스트의 활용 범위를 향상시킨다. 이를 위하여 본 논문에서는 모바일 컨텍스트 종류를 설명하고, 이를 보여주기 위한 컨텍스트 Visualizer의 설계를 제시한다. 또한 설계 모델을 기반으로 구현한 프로토타입을 보여주고, Visualizer의 활용을 제시함으로써 연구의 실효성을 보여준다.

폴리머 디스퍼전 SBR과 고로슬래그 미분말 및 플라이애시를 사용한 폴리머 시멘트 모르타르의 기초적 성질에 관한 연구

김완기 ( Kim Wan-ki ),조영국 ( Jo Young-kug ) 한국건축시공학회 2021 한국건축시공학회지 Vol.21 No.1

본 연구는 고로슬래그 미분말 및 플라이애시를 혼입한 PCM의 플로, 압축강도 및 휨강도 개선 정도를 평가하고자 하였다. 실험을 위한 공시체는 SBR 폴리머 디스퍼전, 혼화재료 2종류, P/C 5가지 (0, 5, 10, 15 및 20%), 혼화재 혼입률 6가지 (0, 3, 5, 10, 15 및 20%)로 변화시켜 PCM을 제작하였으며, 비교를 위하여 보통 시멘트 모르타르도 제작하였다. 본 연구결과, PCM의 플로는 보통 시멘트 모르타르에 비해 크게 개선되었으나, 고로슬래그를 혼입한 경우 플로가 약간 저하하였으며, 플라이애시를 혼입한 경우에는 PCM과 비슷한 경향을 보였다. 또한 혼화재를 혼입한 PCM의 압축강도는 상당히 개선되었으나, 휨강도는 일부를 제외하면 개선효과가 거의 나타나지 않았다. 본 연구에서 BF와 FA 혼입률 10%-15%의 SBR를 사용한 PCM의 압축강도 개선에는 P/C 10%, 휨강도의 개선을 위해서는 P/C 20%를 각각 최적 배합으로 제안할 수 있었다. The purpose of this study is to evaluate the improvement of flow, compressive and flexural strengths of polymer cement mortar(PCM) using SBR latex mixed with blast-furnace slag and fly ash. The test specimens were prepared with SBR polymer dispersion, two types of admixture (blast-furnace slag and fly ash), five polymer-cement ratios (P/C; 0, 5, 10, 15 and 20%), and six admixture contents (0, 3, 5, 10, 15 and 20%), plain cement mortar was also made for comparison. From the test results, the flow of PCM was significantly improved compared to ordinary cement mortar, but the flow was slightly reduced when mixed with blast-furnace slag, and the flow was similar to PCM when mixed with fly ash. In addition, the compressive strength of PCM mixed with admixtures was significantly improved, but the flexural strength did not improve except for some mortars. It can be stated that the optimum mix proportions of PCM using SBR with admixture contents 10 to 15% and P/C 10% for the compressive strength improvement, and P/C 20% for flexural strength improvement are recommended respectively in this study.

비스페놀 A형 에폭시수지 혼입 폴리머 시멘트 모르터의 강도특성 및 자기수복기능 검토

김완기(Kim Wan-Ki) 대한건축학회 2004 大韓建築學會論文集 : 構造系 Vol.20 No.11

Concrete materials present unresolved durability issues. Life cycle costs are high and damage can be unsightly and unpredictable. If it is developed any smart cement composites which can self-repair internal cracks due to mechanical loading, the durability of concrete materials are remarkably improved. The purpose of this study is to ascertain self-rehabilitation function of epoxy-modified mortars without hardener. The epoxy-modified mortars without hardener are prepared with various polymer-cement ratios, subjected to different curing conditions, and tested for flexural and compressive strengths. And then, the epoxy-modified mortars without hardener in standard cure are evaluated the self-rehabilitation function through strength test after preloading at a 90 percentage of maximum compressive load.<br/> As a result, the strengths of epoxy-modified mortars without hardener are remarkably improved at the range of 5 to 15% of polymer cement ratios in comparison with unmodified mortar. Among 3types of the curing conditions, the standard cure are recommended as a optimal curing condition of the epoxy-modified mortars. The strength of epoxy-modified mortars without hardener are improved because of the self-rehabilitation function of cracks during curing after preloading. Accordingly, it is considered that the epoxy-modified mortars without hardener may be used as intelligent materials in repair work for deteriorated reinforced concrete structures.

국제학술회의 개최일정 안내 및 국제학회지 주요기사

김완기(Wan-Ki Kim),김희선(Hee-Sun Kim) 한국콘크리트학회 2011 콘크리트학회지 Vol.23 No.4

안전한 차량 OTA 소프트웨어 업데이트 Design

김완기(WAN- KI KIM) 한국정보과학회 2021 한국정보과학회 학술발표논문집 Vol.2021 No.12

가열양생법에 의한 경화제 무첨가 에폭시수지 혼입 PCM의 강도 발현

김완기(Kim Wan-Ki),조영국(Jo Young-Kug) 대한건축학회 2010 大韓建築學會論文集 : 構造系 Vol.26 No.10

The epoxy resin without hardener can harden by a ring-opening reaction in the presence of the alkalies produced by the hydration of cement in epoxy-modified mortars and concretes. This paper investigates the effect of curing conditions on the strength improvement of polymer-modified mortars using bisphenol A-type epoxy resin without hardener. The polymer-modified mortars using epoxy resin are prepared with various polymer-cement ratios, and subjected to ideal, water, dry and heat cures. In the heat cure, the epoxy-modified mortars are sealed or unsealed with a PVDC (polyvinylidene chloride) film. The epoxy-modified mortars are tested for flexural and compressive strengths at desired curing methods. The microstructures of the epoxy-modified mortars are also observed by scanning electron microscope. The effects of curing conditions on the strength development of the epoxy-modified mortars are examined. From the test results, the marked effectiveness of the heat cure under the PVDC film sealing against the development of the strength of the epoxy-modified mortar without the hardener is recognized. The compressive and flexural strengths of 1-day-80℃ heat-cured, PVDC film-sealed epoxy-modified mortars without hardener reach 23 to 30㎫ and 6.4 to 7.8㎫ respectively, and are about two times of unmodified mortar. Such high strength development of the epoxy-modified mortars may be achieved by the dense microstructure formation by cement hydrates and the hardening of the epoxy resin in the mortars.

환경부하저감형 고내구성 폴리머 시멘트계 재료를 이용한 철근 부식저감기술

김완기(Kim, Wan-Ki),정승진(Chung, Seung-Jin) 한국생태환경건축학회 2010 한국생태환경건축학회 논문집 Vol.10 No.5