• 제목/요약/키워드: Repairing Materials

검색결과 211건 처리시간 0.027초

철근콘크리트 구조물의 보수 공법연구(II) - 휨 거동 비교 - (Studies on Repair of Reinforced Concrete Structures(II) - Their Influence on Flexural Performance -)

  • 김병국;신영수;홍기섭;이차돈;최완철
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 1995년도 봄 학술발표회 논문집
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    • pp.219-224
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    • 1995
  • A series of 15 reinforced concrete beams was tested to explore the effects of polymer repair on damaged beams. The key parameters for this study were the repair materials, repair methods, repair depths and repair locations. The repaired specimens failed by a typical flexural mode, showing minor interface failure. The results show that epoxy, polyester resins and latex modified cementitous mortars are effective for repairing the concrete beams. The results also show that the depth and the location of the repair do not change significantly the flexural preformance of the repaired beams.

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에폭시 모르터로 보수한 손상을 입은 RC 보의 휨 거동 (Flexural Behavior of Damaged RC Beams Repaired with Epoxy Mortar System)

  • 조하나;신영수;홍건호;정혜교
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 1999년도 봄 학술발표회 논문집(I)
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    • pp.762-767
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    • 1999
  • This paper presents an experimental study on flexural behavior of damaged RC beams repaired with epoxy mortar system. The main test variables are repair length and depth. A series of 7 specimens was tested to show the corresponding effect of each variables on maximum load capacity, load-deflection relationship, and failure mode. The results of this study shows that flexural behavior of repaired RC beams changes as the repair length and depth is getting longer and deeper, so that the tension strength of repairing materials should be considered in the courses of repair design.

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DFRCC의 보강두께에 따른 전단보강 RC 부재의 휨 거동에 관한 실험적 연구 (Experimental Study of Flexural Behavior in RC Beams with strrup on Repair Thickness of DFRCC)

  • 김장호;임윤묵;이경민;박정호;홍종석
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 2005년도 추계 학술발표회 제17권2호
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    • pp.539-541
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    • 2005
  • The purpose of this study is to accurately understand the flexural behavior in RC beam with strrup on repair thickness of DFRCC. Using a four-point bending test, the shear strengths and shear stress-deflection relations of DFRCC repair RC specimens are obtained. The results show that DFRCC can be effectively used for repairing materials for concrete structures.

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CFRP 적층판으로 보강된 철근콘크리트보의 신뢰성평가 (Reliability Assessment of Reinforced Concrete Beams Strengthened by CFRP Laminates)

  • 조효남;최영민
    • 한국전산구조공학회:학술대회논문집
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    • 한국전산구조공학회 1994년도 가을 학술발표회 논문집
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    • pp.160-166
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    • 1994
  • In general, the problems of strengthening and repairing of deteriorated or damaged reinforced concrete members are usually worked out in situ by externally bounding steel plates using epoxy resins, which has been recognized to be one of effective and convenient methods. But the disadvantages of strengthening/repairing concrete members with externally bonded steel plates include ; (a) deterioration of the bond at the steel-concrete interface caused by the corrosion of steel ; (b) difficulty in manipulating the plate at the construction site ; (c) improper formation of joints, due to the limited delivery lengths of the steel plates ; and etc. Therefore these difficulties eventually have led to the concept of replacing the steel plates by fiber-reinforced composite sheets which are characterized by their light weight, extremely high stiffness, excellent fatigue properties, and outstanding corrosion resistance. In the paper, for the reliability assessment of reinforced concrete beams externally strengthened by carbon fiber plastic(CFRP) laminates, an attempt is made to suggest a limit state model based on the strain compatibility method and the concept of fracture mechanics. And the reliability of the proposed models is evaluated by using the AFOSM method. The load carrying capacity of the deteriorated and/or damaged RC beams is considerably increased. Thus, it may be stated that the post-strengthening of concrete beams with externally bonded CFRP materials may be one of very effective way of increasing the load carrying capacity and stiffeness characteristics of existing structures.

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초기 양식건축물의 보수.보존에 관한 연구 -국가 지정 교회건축 문화재의 현황조사를 중심으로- (A Study on Repairing and Preservation of the Early Western Style Architecture in Korea - Focused on the Case Study on the Church Buildings Which are Registered as National Cultural Properties -)

  • 김정신
    • 건축역사연구
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    • 제10권2호
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    • pp.55-71
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    • 2001
  • This study reviewed the preservation status of the Early Western Style Architecture in Korea based on the on-site research of church buildings which are registered as National Cultural Properties. I have investigated 21 church buildings regarding the frequency, content and concept of restoration. The results are summarized as follows First, the churches have been restored extensively in every 17 years on the average. Second, the main restorations are replacement of bricks, painting, waterproofing, repair of roof and timber. And the main changes are extension of plan, removal of Interior posts, and replacement of floor. Third, the main concept of restorations are historical restoration(62%), critical restoration(23%), stylistic restoration(14%). Forth, the category of restoration have been changed, that is extending of incompletion (1st stage), functional improvement and extension of the span of life(2nd stage), improvement of facilities(3rd stage), restoration to the original state and conservation(4th stage). Fifth, the issues of repairing techniques are revival and replacement of weathered bricks, the removal of painting, and structural reinforcement. This study will be able to be used as the fundamental materials to improve the techniques of restoration of Early Western style masonry buildings.

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충격 손상된 카본/에폭시 복합재 구조의 패치 접착 보수 방안 적용 후 압축 강도 특성 평가 (A Study on Compressive Strength of Carbon/epoxy Composite Structure Repaired with Bonded Patches after Impact Damage)

  • 공창덕;박현범;임성진;신철진
    • Composites Research
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    • 제23권5호
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    • pp.15-21
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    • 2010
  • 본 연구에서는 손상된 복합재 구조의 유지 보수 방안에 대한 연구를 수행하였다. 복합재료 구조의 손상 수리 방안을 제시하고 수리 절차를 카본/에폭시 적층판 복합재 구조에 적용하여 시편 시험 및 수치 해석을 통해 분석하였다. 손상은 중량 낙하식 충격 시험기를 활용하여 복합재 구조 시편에 충격 손상으로 모사하였다. 손상된 복합재 적층판 구조는 충격 손상 부위 제거 후 외부 패치 수리 기법을 적용하여 수리하였다. 충격 손상 후 유지 보수된 시편과 손상이 없는 시편의 압축 강도를 실험적 및 해석적으로 비교 분석하였다. 이를 바탕으로 유지 보수된 시편의 강도 회복 능력을 고찰하였다.

System identification of arch dam model strengthened with CFRP composite materials

  • Altunisik, A.C.;Gunaydin, M.;Sevim, B.;Adanur, S.
    • Steel and Composite Structures
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    • 제25권2호
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    • pp.231-244
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    • 2017
  • This paper presents the structural identification of an arch dam model for the damaged, repaired and strengthened conditions under different water levels. For this aim, an arch dam-reservoir-foundation model has been constructed. Ambient vibration tests have been performed on the damaged, repaired and strengthened dam models for the empty reservoir (0 cm), 10 cm, 20 cm, 30 cm, 40 cm, 50 cm and full reservoir (60 cm) water levels to illustrate the effects of water levels on the dynamics characteristics. Enhanced Frequency Domain Decomposition Method in the frequency domain has been used to extract the dynamic characteristics. The dynamic characteristics obtained from the damaged, repaired and strengthened dam models show that the natural frequencies and damping ratios are considerably affected from the varying water level. The maximum differences between the frequencies for the empty and full reservoir are obtained as 16%, 33%, and 25% for damaged, repaired and strengthened model respectively. Mode shapes obtained from the all models are not affected by the increasing water level. Also, after the repairing and strengthening implementations, the natural frequencies of the arch dam model increase significantly. After strengthening, between 46-92% and 43-62% recovery in the frequencies are calculated for empty and full reservoir respectively. Apparently, after strengthening implementation, the mode shapes obtained are more acceptable and distinctive compared to those for the damaged model.

도토기 보존처리에 사용된 복원재료 연구 (Research of Restoration Material in Pottery and Porcelain Conservation)

  • 양필승;문선영;박기정
    • 한국문화재보존과학회:학술대회논문집
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    • 한국문화재보존과학회 2005년도 제22회 학술대회 발표 논문집
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    • pp.179-184
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    • 2005
  • Materials used for repairing and restoring both pottery and porcelain are practically organic, which makes the analysis procedure difficult in the course of time. It is, however, important in the field of conservation to analyze the material applied in the past. In consequence, this research will examine the components of the restoration materials collected in the process of ceramic conservation: the fillings using SEM-EDS and FT-IR; retouching materials; the adhesive used between the filling and retouching material.

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라미네이트 강도 특성에 미치는 Thermal Aging의 영향 (Effect of Thermal Aging on The Strength of Laminate Composites Structure)

  • 정연운;김국진;한중원;김윤해
    • 한국복합재료학회:학술대회논문집
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    • 한국복합재료학회 2002년도 추계학술발표대회 논문집
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    • pp.24-28
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    • 2002
  • Composite reinforced fiber materials are used in lots of fields such as a part of aeronautic space, ship, machinery and so on because can make structure wished for necessary condition by control fiber direction and laminated sequence. As the use of advanced composites increase, specific techniques have been developed to repair changed composite structures. In order to repair the damaged part production high quality composite reinforced fiber are completed by control the surrounding temperature and press in autoclave. The quality is influenced heat exposure degree by chemical reaction for precessing. This study considerated influence limit of using by repair structure part and change of properties according to heat exposure degree for repairing.

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F-5E/F 15% SPAR KIT 용 폴리우레탄 캐스팅 윙 페어링 소재 및 공정개발 (A Study on materials and manufacturing process of polyurethan fairing parts for F-5E/F 15% spar kit)

  • 김국진;문영진;한중원;김영생;곽준영;최재성
    • 한국복합재료학회:학술대회논문집
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    • 한국복합재료학회 2002년도 추계학술발표대회 논문집
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    • pp.193-197
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    • 2002
  • Polyurethane casting wing fairings included in F-5E/F 15% spar kit are to be installed on aircraft wing surfaces and used for compensating the changes of the aerodynamic configuration by the leading edge extension fairings. These fairing are mandatory items in repairing wing areas and was imported from foreign supplier with long term delivery and high cost. Accordingly, local manufacturing is necessary to get rid of above disadvantages such as long term delivery and high cost. Basic properties test of specimen to be developed and part's requirements after localization was taken and its values were similar or higher when comparing with the original's even in low temp test at -55C. Casting mold process was used to manufacture the polyurethane fairings and its demensional stability & physical condition was proper and met to the related specification and drawing's requirements

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