• 한국농공학회:학술대회논문집
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• 한국농공학회 1999년도 Proceedings of the 1999 Annual Conference The Korean Society of Agricutural Engineers
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• pp.231-238
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• 1999

Most of the irrgation structures are shortage of feasible facility management. The surveyed data to irrigation structures related to maintenance record were built and interface program between GIS and database were developed . It was conducted to develope a system for safe appraisal and repair works on agricultural irrigation structures. The system assisting onsite field investigation and determining the typical rehabilitation method of typical agricultural structural problems such as fractures and cracks of members was developed.

• Composites Research
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• 제19권1호
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• pp.43-48
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• 2006

High performance fiber reinforced cement composites have better performances than traditional cement based materials, therefore, have been expected as new construction applications such as the materials for construction & bridge structure, repair and rehabilitation applications, anti-collapse applications, anti-noise applications etc. However, they have lots of the problems such as material design, fabrication method and structural analysis. Also, the most serious problems of High performance fiber reinforced cement composites have been expensive initial cost, lack of long-term exposure data. As a result, it is needed that the efforts for lowering the initial cost and accumulation of long-term exposure. There has been hardly assessment results of life cycle cost for HPFRCC in construction field, but some papers showed that total life cycle cost could be profitable if the initial cost could be reduced.

• 콘크리트학회논문집
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• 제13권5호
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• pp.430-437
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• 2001

최근 교량상 통과하중의 증대 및 교통량증대로 공용중의 교량의 바닥판은 가혹한 하중하에서 펀칭등의 파괴가 발생하여 사용상에 중대한 영향을 미치고 있는 실정이다. 이로 인한 바닥의 보수나 교체공사등이 급격히 증가되어 신속 간편하며, 보수시 교통통제를 최소화 할 수 있고 또한 신뢰성이 있는 바닥판 시공법이 필요하게 되었다. 따라서 본 연구의 목적은 교량구조물 바닥판의 신설/교체공사에 있어서 신속한 시공과 신뢰성 있는 품질관리, 교통통제의 최소화를 위해 공장 또는 제작장에서 바닥판 구조물의 주부재로서 I형강을 배치하고 거푸집(저판)을 조립하여 패널을 제작한 후 현장에서는 패널의 설치 및 연결부에 콘크리트를 타설하여 바닥판을 시공하는 공법을 개발하는데 그 목적이 있다. 따라서 본 연구에서는 I형강 합성바닥판 개발에 필요한 I형강 자체의 역학적, 구조적 특성에 대하여 기초적인 물성 실험인 정적. 피로성능 실험을 수행하였으며, I형강 합성바닥판 및 유사한 성능의 바닥판 시험체를 제작하여 정적실험을 수행 비교하였다. 그리고 본 실험 연구 결과 I형강 합성바닥판의 우수성을 확인하였다.

• 한국안전학회지
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• 제17권2호
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• pp.85-91
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• 2002

A research on the performance of retrofit anchors was conducted using adhesives for rehabilitation. From the pull-out tests of the chemical anchors, the effect of the hole diameter, spacer, temperature, moisture, embedment depth, and aging time were investigated. The spacer did not directly increased the pull-out load hilt increased post-yielding resistance therefore the ductility of the retrofit anchors. When the hole was cleaned and dried after the immersion, the pull-out load was greatly increased compared to the wet hole. A design equation was unposed depending on the embedment depth of the anchor bolt.

• 한국방재안전학회논문집
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• 제5권1호
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• pp.43-47
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• 2012

기반시설물의 자산관리란 기반시설 운영을 지원하는 기반시설물에 대한 상태 및 성능을 평가하고 적절한 유지보수보강을 수행하여 수명을 연장시키며, 종국적으로 국가예산을 절감할 수 있는 모든 수단을 강구하는 유지운영관리의 전사적인 체계라 할 수 있다. 이 자산관리의 범위에는 관리조직, 관리인력, 그리고 조직의 목표와 슬로건, 장단기적인 사업 계획 뿐만 아니라 정보 및 데이타 등의 전체적인 것을 아우르고 있다. 기반시설 자산관리에서의 핵심은 운영 효율성과 보수 작업성, 그리고 시설 안전성 및 재해 위험성, 그리고 조직관리 및 단계적인 정책 수립을 위한 의사결정 기준수립이 관건이 된다. 따라서 본 연구에서는 일반적인 기반시설 자산관리분석위험도 기법에 대한 개괄적 소개와 더불어 BRE(Business Risk Exposure)를 통한 위험도 평가 및 기반시설 자산관리차원의 위험평가방법에 대한 전반적인 절차를 구성하여 제시하였다. 또한 사회기반시설유지관리상의 의사결정에서 가장 중요시 될수 있는 최적유지관리시기 및 비용에 대한 리스크 관리의 필요성을 제시하고자 하였다.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1999년도 학회창립 10주년 기념 1999년도 가을 학술발표회 논문집
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• pp.597-600
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• 1999

Recitly, the use of sea-sand is increasing in the construction due to the rapid reduction of river-sand. In that case, one of the major problem is that a sand salt in sea-sand induce the corrosion of embedded reinforcing bar in concrete. In addition, the deterioration of concrete quality arises a social problem in the durability of reinforced concrete. This research is aimed at providing the data for the control of design method of repair and rehabilitation in the reinforced concrete structure by means of the evaluation of structural performance due to corrosion.

• 한국구조물진단유지관리공학회 논문집
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• 제6권2호
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• pp.135-143
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• 2002

This study is to investigate its use by applying stainless steel wire mash reinforcement method of construction, which is newly developed, on the high strength concrete beam mixed with polymer-steel fiber. In this test, it is investigated and observed such as follows: the ultimate load, the initial flexure crack load, the initial diagonal tension crack load, the relation between load and deflection, load-strain relation, and also crack growth and fracture aspect by increasing load. The results of this test are; first, the stainless steel wire showed some useful reinforcement effects in multiplying the steel's resisting force of moment to the tensile force of beam or slab: second, the promoting strength and internal force was made in the process of the integration at the same reaction by using the penetrating polymer-mortar with an excellent durability and physical property. On the basis of this results, because such instances in applying stainless steel wire Mash reinforcement method of construction have been few so far, through the experimental investigation such as this test over and over again, the efficient and useful method must be developed for the practice.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 2008년도 정기 학술대회
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• pp.387-390
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• 2008

The importance of the life cycle cost analysis for construction projects of bridge has been recognized over the last decades. Accordingly, theoretical models, guidelines, and supporting softwares have been developed for the life cycle cost analysis of bridges. However, it is difficult to predict life cycle cost considering uncertainties precisely. This paper presents methodology for optimal design of substructure for a steel box bridge. Total life cycle cost for the service life is calculated as sum of initial cost, damage cost considering uncertainty, maintenance cost, repair and rehabilitation cost. The optimization method is applied to design of a bridge substructure with minimal cost, in which the objective function is set to life cycle cost and constraints are formulated on the basis of Korean Bridge Design Specification. Initial cost is calculated based on standard costs of the Korea Construction Price Index and damage cost on the damage probabilities to consider the uncertainty of load and resistance. An advanced first-order second moment method is used as a practical tool for reliability analysis using damage probability. Maintenance cost and cycle is determined by a stochastic method and user cost includes traffic operation costs and time delay costs.

• 상하수도학회지
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• 제29권3호
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• pp.395-406
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• 2015

This research carried out an analysis on input cost and leakage reduction effect by leakage reduction method, focusing on the project for establishing an optimal water pipe network management system in the Taebaek region, which has been executed annually since 2009. Based on the result, optimal cost-benefit analysis models for water distribution network rehabilitation project were developed using DEA(data envelopment analysis) and multiple regression analysis, which have been widely utilized for efficiency analysis in public and other projects. DEA and multiple regression analysis were carried out by applying 4 analytical methods involving different ratios and costs. The result showed that the models involving the analytical methods 2 and 4 were of low significance (which therefore were excluded), and only the models involving the analytical methods 1 and 3 were suitable. From the result it was judged that the leakage management method to be executed with the highest priority for the improvement of revenue water ratio was installation of pressure reduction valve, followed by replacement of water distribution pipe, replacement of water supply pipe, and then leakage detection and repair; and that the execution of leakage management methods in this order would be most economical. In addition, replacement of water meter was also shown to be necessary in case there were a large number of defective water meters.

• 대한정형외과 초음파학회지
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• 제2권2호
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• pp.53-61
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• 2009

목적: 관절경적 회전근 개 봉합술 후 주기적 초음파 추적검사의 임상적 유용성과 회전근 개 파열크기 및 봉합방법에 따른 재파열의 빈도 및 시기를 밝히고자 한다. 대상 및 방법: 2008년 1월부터 6월까지 본원 정형외과에 내원하여 회전근 개 파열로 관절경적 치료를 시행한 환자 52명 중 6개월 이상 추시 관찰한 29명을 대상으로 초음파 검사를 시행한 후 관절경적 시술을 이용하여 비교하였으며, 수술 후 2주, 6주, 3개월 및 6개월에 회전근 개의 건재 상태를 초음파를 이용하여 관찰하였다. 결과: 전층 회전근 개 파열 중 소 및 중 파열은 10예로, 이중 활차 교량 봉합술(double pully suture bridge technique, DPSB)을 시행하였으며 2예(20%)에서 재파열(retear) 소견을 확인할 수 있었으며, 대 및 광범위 파열은 19예로, 건-건 봉합술을 시행한 6예 모두(100%)에서, 건-건 봉합술 및 골-건 봉합술을 시행한 2예 중 1예(50%)에서, 이중 활차교량 봉합술을 시행한 11예 중 6예(55%)에서 재파열 소견을 확인할 수 있었다. 추시 관찰의 시기에 따른 재파열은 수술 후 2주에서 6주 사이에 1예(7%), 6주에서 3개월 사이에 10예(66%), 3개월에서 6개월 사이에 4예(27%)가 관찰되었다. 결론: 관절경적 회전근 개 봉합술 후 주기적 초음파 추적검사는 재파열 유무 및 재파열의 시기를 확인하는데 유용하며, 술 후 재활치료의 지침을 설정하는데 도움을 줄 수 있을 것으로 생각한다.