• 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.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2003년도 학술.기술논문 발표회
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• pp.37-40
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• 2003

This present paper mainly contains adhesion part disconnection type exposure composition waterproof method using embossing PVC sheet. The existing polymer resin coating and sheet waterproofing construction method have, however, some weak point such as being decrease life cycle of concrete with water leaking from materials be affected by crack and movement dash bond concrete through the whole-adhere construction. Above the reason, this paper has particular method increasing crack-defending performance from stress occurred concrete movement by part disconnection, adds maintain waterproofing performance subordinate sheet, that can be contributed a convenience of maintenance which is decreasing industrial waste and repair construction cycle through the part repair in case of leaking water.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2003년도 학술.기술논문발표회
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• pp.37-40
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• 2003

This present paper mainly contains adhesion part disconnection type exposure composition waterproof method using embossing PVC sheet. The existing polymer resin coating and sheet waterproofing construction method have, however, some weak point such as being decrease life cycle of concrete with water leaking from materials be affected by crack and movement dash bond concrete through the whole-adhere construction. Above the reason, this paper has particular method increasing crack-defending performance from stress occurred concrete movement by part disconnection, adds maintain waterproofing performance subordinate sheet, that can be contributed a convenience of maintenance which is decreasing industrial waste and repair construction cycle through the part repair in case of leaking water.

• 정보저장시스템학회논문집
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• 제2권4호
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• pp.230-235
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• 2006

The machine locking system is an important device for the safety of persons using the machine. In this study, a locking system using electromagnetic fields is proposed to decrease the defects and the cost for repairing and maintenance of the existing locking system using structural mechanism. We analyze the electromagnetic locking system and calculate the generated force considering direction by the finite element method. Also, we set up two design domains for the topology optimization; first domain is optimized to reduce the volume and the other is optimized to maximize the generated force keeping the volume, especially. The optimal design is obtained by integration of the two optimized results. An improved design is obtained by the optimal topology and it is confirmed by comparison with the initial locking system.

• Structural Monitoring and Maintenance
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• 제1권3호
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• pp.323-338
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• 2014

In this study a new innovative method of earthquake-resistant strengthening of reinforced concrete structures is presented for the first time. Strengthening according to this new method consists of the construction of steel fiber ultra-high-strength concrete jackets without conventional reinforcement which is usually applied in the construction of conventional reinforced concrete jackets. An innovative solution is proposed also for the first time that ensures a satisfactory seismic performance of existing reinforced concrete structures, strengthened by using composite materials. The weak point of the use of such materials in repairing and strengthening of old R/C structures is the area of beam-column joints. According to the proposed solution, the joints can be strengthened with a steel fiber ultra-high-strength concrete jacket, while strengthening of columns can be achieved by using CFRPs. The experimental results showed that the performance of the subassemblage strengthened with the proposed mixed solution was much better than that of the subassemblage retrofitted completely with CFRPs.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1995년도 가을 학술발표회 논문집
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• pp.344-349
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• 1995

In recent years, the most common bridges are showed a decrease of duriability in quick times of 10~20 years after construction. Therefore, the project of maintenance and management is located a important subject more and more. The maintanence-management of bridges begin from inspection of bridge and this accupy more important part with repairing-reinforcing method. In a point of view liked this, the purpose of this paper is to propose the most rational and useful method for the maintance-management of bridges with comparing and examming inspection kind inspection frequency and judge standard etc. that manage the each organization of Korea and Japan. Also in the bases of this result, hereafter, it will propose the standard idea for the organization etc. of databank of the bridges.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2017년도 추계 학술논문 발표대회
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• pp.223-224
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• 2017

In this study, various materials such as epoxy material, urethane material, cement material, and acrylic material are used to solve the water leakage occurring in underground structures. However, in the reality that the durability is insufficient and the effect is insufficient, it is aimed to improve the repairing effect by using cement and acrylics in combination. As a first study, we tried to verify the performance of improve the performance by checking the product properties according to the composition ratio of polyacrylic resin. Polyacrylic resin is evaluated in three different composition ratios. When the material is selected for polyacrylic resin, it is applied to the field to understand the maintenance effect and durability.

• 한국구조물진단유지관리공학회 논문집
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• 제23권2호
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• pp.10-19
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• 2019

염해에 콘크리트 구조물은 사용기간의 증가에 따라 내구성에 문제가 발생하므로 보수를 포함한 유지관리가 필수적이다. 일반적으로 결정론적인 방법으로 내구수명이 결정되고 이에 따라 유지관리비가 평가되고 있으나, 확률론적 유지관리 기법을 고려할 경우 연속적인 보수비용이 평가되므로 합리적인 유지관리가 가능하다. 기존의 확률론적 유지관리 기법에서는 정규분포만 고려되었으나, 본 연구에서는 초기 내구수명 및 보수에 따른 수명-확률함수에 로그함수를 고려할 수 있도록 개선되었으며, OPC 및 GGBFS를 사용한 콘크리트에 대하여 보수비용을 평가하였다. 로그 함수를 가지는 수명-확률함수는 중앙값 이전보다 이후에 미치는 영향이 지배적이므로 초기 내구수명 분포에 유리하며 전반적으로 낮은 보수비용을 도출할 수 있다. GGBFS를 사용한 콘크리트는 OPC 콘크리트 비하여 높은 내구수명과 낮은 보수횟수를 통하여 30% 수준으로 보수비가 감소하였다. 본 연구에서 도출된 확률론적 유지관기 기법은 정규분포 뿐 아니라 로그분포를 가지는 수명-확률함수를 초기 및 다양한 보수시기에 적용할 수 있는 장점을 가지고 있으며, 더욱 합리적인 보수비용을 도출할 수 있다.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2018년도 춘계 학술논문 발표대회
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• pp.345-346
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• 2018

In this study, various materials such as epoxy material, urethane material, cement material, and acrylic material are used to solve the water leakage occurring in underground structures. However, in the reality that the durability is insufficient and the effect is insufficient, it is aimed to improve the repairing effect by using cement and acrylics n combination. As a first study, we tried to verify the performance of rapid micro cement and cement paste and to improve the performance by checking the product properties. Three types of micro cement are evaluated. Three types of micro cement are used: fiber inclusion, fiber unfolding, and cement paste. When the material is selected for micro cement, it is applied to the field to understand the maintenance effect and durability.

• 한국주거학회:학술대회논문집
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• 한국주거학회 1994년도 학술발표대회논문집 하
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• pp.43-49
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• 1994

In Korea, the rental apartments for low-income bracket have greatly been built and are being built now. But their management system is quite unstable and the residents' participation in the management is excluded throughly from the beginning. As a result, there are increasing complaints about their low quality of management as well as a self-righteous managerial behavior by the housing company. Therefore, it is required to be managed by residents in the rental apartmenr and especially the organization of management, such as decision making-executing-audition body, should be operated by the residents. To achieve this purpose, the management law should be consolidated into one and the method o imposing the expenses of repairing and maintenance should be improved by The Ministry of Construction and Transportation.