• Title, Summary, Keyword: Deterioration

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Development of Deterioration Diagnosis System for the R/C Structures - Mainly on Cause of Deterioration - (철근콘크리트 구조물의 열화 진단시스템 개발 - 열화요인 진단을 중심으로 -)

  • 이장화;박홍석;유영찬;김도겸;송영철
    • Proceedings of the Korea Concrete Institute Conference
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    • pp.243-248
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    • 1994
  • The purpose of this study is to develop Deterioration Diagnosis System for the Reinforced Concrete Structure which can be used preliminary in determining the factors causing deterioration by simple inspection and mapping of the indicators of deterioration. Total 29 items compromising material, structural and constructional factors causing deterioration were considered in this system. Also the indicators of deterioration were subdivided into 54 items such as concrete crack pattern and steel corrosion etc. Each indicator of deterioration was quantatified by allocating and giving grade to each item which has extra weight according to its conscquence. Satisfactory results were obtatined by applying this Diagnosis system to the indicators of deterioration in ref. [3]. Further research was required on the indicators of deterioration in construction site to enhance the field applicability of this system.

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Development of the Evaluation Techniques of the Deterioration for the Rural House (농촌주택 개량을 위한 노후화 진단 방안)

  • 정남수;이정재;김한중;윤성수;박미정
    • Magazine of the Korean Society of Agricultural Engineers
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    • v.43 no.1
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    • pp.106-115
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    • 2001
  • This study attempted to make evaluation model of deterioration for the rural house. defined the deterioration of rural house as the two categories. First is the physical deterioration which is affected by physical faults and the second is the social deterioration which is affected by change of environments. As a results, physical deterioration model was developed by types of rural house, and social deterioration model was considered to reverse function of satisfaction of a resident.

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Evaluation of Deterioration on Steel Bridges Based on Bridge Condition Ratings

  • Park, Chan-Hee
    • Corrosion Science and Technology
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    • v.3 no.4
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    • pp.166-171
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    • 2004
  • Recent developments in Bridge Management Systems (BMS) and in Life-Cycle Cost (LCC) of bridges, have raised the need for evaluation procedure of future condition (Deterioration) of a bridge. Predicting future deterioration is not an easy task due to limited past data to extrapolate from and also due to difficulty in measuring actual deterioration such as section loss of steel on an actual steel bridge. Also, increase in live load and reduction of resistance are random variables, thus a probabilistic approach should be adopted for determining the future deterioration. Due to difficulties in evaluation of future deterioration on steel bridges, accepting uncertainties within a reasonable error, a deterministic procedure using bridge condition rating can be a useful tool for projection of future condition of bridges to identify repair and maintenance needs. The object of this paper is to determine applicability of evaluating deterioration of steel bridge components based on Bridge condition ratings. Bridge condition ratings of bridge components show wide variation for bridges of same age and does not directly correlate well with the age of the bridge and/or deterioration of the bridge. High uncertainty can be reduced by breaking down the rating and by sensitivity analysis. From refined condition rating data, generalized deterioration profile of structures based on age can be derived. Examples are shown for sample bridges in USA. Approximately, 3,000 short to medium span steel bridges were listed in the inventory database. Results show wide variation of rating factors but by subdividing the Bridge condition ratings for various categories general deterioration profiles of steel bridges can be determined.

Making Method of Deterioration Map and Evaluation Techniques of Surface and Three-dimensional Deterioration Rate for Stone Cultural Heritage (석조문화유산의 손상지도 제작방법과 표면 및 3차원 손상율 평가기법)

  • Jo, Young-Hoon;Lee, Chan-Hee
    • Journal of Conservation Science
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    • v.27 no.3
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    • pp.251-260
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    • 2011
  • This study focus on the suggestion of standard legend, the process system on making method of deterioration map, the development of crack index (CI), and the evaluation techniques of surface and 3D deterioration rate for stone cultural heritage. The standard legends of deterioration forms were made using a common graphic program after crack, blistering, scaling, break-out, granular disintegration, and perforation were subdivided. The deterioration map improved accuracy and reliability on deterioration range using 3D digital restoration and high resolution photograph mapping technique. Also, quantitative deterioration evaluation of stone cultural heritage was carried out developing the crack index, and the 3D deterioration rate of a break-out part was calculated by virtual restoration modeling. As a quantitative deterioration evaluation of Magoksa Temple stone pagoda based on the results described above, the north face showed high deterioration rate of bursting crack (1.70), hair crack (1.34), scaling (20.2%) and break out (13.0%), and the 3D deterioration rate of first roof stone was 6.7%.

Resistance of concrete made with air- and water-cooled slag exposed to multi-deterioration environments (서냉 및 급냉슬래그를 적용한 콘크리트의 복합열화 저항성)

  • Lee, Seung-Tae;Park, Kwang-Pil;Park, Jung-Hee;Park, Se-Ho
    • International Journal of Highway Engineering
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    • v.20 no.3
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    • pp.11-18
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    • 2018
  • PURPOSES : Durability of concrete is traditionally based on evaluating the effect of a single deterioration mechanism such as freezing & thawing action, chloride attack, carbonation and chemical attack. In reality, however, concrete structures are subjected to varying environmental exposure conditions which often results in multi-deterioration mechanism occurring. This study presents the experimental results on the durability of concrete incorporating air-cooled slag(AS) and/or water-cooled slag(WS) exposed to multi-deterioration environments of chloride attack and freezing & thawing action. METHODS : In order to evaluate durable performance of concretes exposed to single- and multi-deterioration, relative dynamic modulus of elasticity, mass ratio and compressive strength measurements were performed. RESULTS :It was observed that multi-deterioration severely affected durability of concrete compared with single deterioration irrespective of concrete types. Additionally, the replacement of cement by AS and WS showed a beneficial effect on enhancement of concrete durability. CONCLUSIONS : It is concluded that resistance to single- and/or multi-deterioration of concrete is highly dependent on the types of binder used in the concrete. Showing the a good resistance to multi-deterioration with concrete incorporating AS, it is also concluded that the AS possibly is an option for concrete materials, especially under severe environments.

Concrete bridge deck deterioration model using belief networks

  • Njardardottir, Hrodny;McCabe, Brenda;Thomas, Michael D.A.
    • Computers and Concrete
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    • v.2 no.6
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    • pp.439-454
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    • 2005
  • When deterioration of concrete is observed in a structure, it is highly desirable to determine the cause of such deterioration. Only by understanding the cause can an appropriate repair strategy be implemented to address both the cause and the symptom. In colder climates, bridge deck deterioration is often caused by chlorides from de-icing salts, which penetrate the concrete and depassivate the embedded reinforcement, causing corrosion. Bridge decks can also suffer from other deterioration mechanisms, such as alkali-silica reaction, freeze-thaw, and shrinkage. There is a need for a comprehensive and integrative system to help with the inspection and evaluation of concrete bridge deck deterioration before decisions are made on the best way to repair it. The purpose of this research was to develop a model to help with the diagnosis of concrete bridge deck deterioration that integrates the symptoms observed during an inspection, various deterioration mechanisms, and the probability of their occurrence given the available data. The model displays the diagnosis result as the probability that one of four deterioration mechanisms, namely shrinkage, corrosion of reinforcement, freeze-thaw and alkali-silica reaction, is at fault. Sensitivity analysis was performed to determine which probabilities in the model require refinement. Two case studies are included in this investigation.

Implementation of Prediction Program for Deterioration Judgment on Substation Power Systems in Urban Railway (도시철도 전력설비의 노후화 판단을 위한 예측 프로그램 구현)

  • Jung, Ho-Sung;Park, Young;Kang, Hyun-Il
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.62 no.6
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    • pp.881-885
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    • 2013
  • In this paper, we present a deterioration judgment model of urban rail power equipment using driving history, the frequency and number of failures. In addition, we have developed a deterioration judgment program based on the derived failure rate. A deterioration judgment model of power equipments on metro system was designed to establish how much environmental factors, such as thermal cycling, humidity, overvoltage and partial discharge. The deterioration rate of the transformers followed the Arrhenius log life versus reciprocal Kelvin temperature (hotspot temperature) relation. The deterioration judgment program is linked to the online condition monitoring system of urban railway system. The deterioration judgment program is based on the user interface it is possible to apply immediately to the urban rail power equipment.

Deterioration Evaluation of Railway Line Segments for Budget Distribution (예산배분을 위한 철도선로구간의 노후도 평가)

  • Kim, Seong-Ho;Choi, Chan-Yong;Na, Hee-Seung
    • Proceedings of the KSR Conference
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    • pp.1802-1809
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    • 2011
  • A distribution method of limited budget for rail line facility improvement is to use investment priorities of rail line segments based on their deterioration. In this paper we present an evaluation method of rail line segment deterioration which can be used to distribute limited budget. Rail line facilities include rail track, crossing, road bed, bridge, tunnel. These facilities deterioration and line shape can affect line segment deterioration. Deterioration evaluation method we present is a weighted sum of each component deterioration scores. The component weight can be obtained from experts using analytic hierarchy process.

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Evaluation Method of Deterioration Grade for Remodeling Old Educational Facilities(III) - Synthetic Judgment Method of Deterioration Grade of Finished Materials - (교육시설(敎育施設)의 리모델링을 위한 구성재료(構成材料)의 노후화(老朽化) 판정기준(判定基準) 작성(作成)(III) - 주요(主要) 마감재료(材料)의 노후도(老朽度) 종합판정방법(綜合判定方法) 제시(提示) -)

  • Seo, Chee-Ho;Choi, Min-Kwon;Choi, Soo-Kyung;Oh, Se-Chul;Kwon, Yong-Kyun
    • Journal of the Korean Institute of Educational Facilities
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    • v.11 no.1
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    • pp.15-23
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    • 2004
  • Deterioration of the educational facilities built before 1985 is a serious situation. The purpose of this study is to present the efficient remodeling method of old educational facilities. This paper, part III, presents the systemic and synthetic judgment method of deterioration grade of finished materials. Evaluation of the deterioration is carried out in every eight classrooms or building elements divided by the use. And classrooms are divided by several parts for example floor, wall and ceiling etc.. The whole deterioration of the building judges the result of every part collectively.

A Condition Based Maintenance Model for Systems with Weibull Distributed Deterioration (와이블 분포로 열화하는 시스템의 상태에 기초한 정비모형)

  • Kong, Myung Bock;Park, Il Gwang
    • Journal of Korean Institute of Industrial Engineers
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    • v.33 no.1
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    • pp.70-75
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    • 2007
  • This paper discusses condition based preventive replacement for deteriorating systems. The system continuouslydeteriorates in time and fails at any deterioration level which is always monitored, It is replaced at failure or atsome deteriorated level preventively before failure. The deterioration process is represented by a Weibulldistribution with a time-linear scale parameter. The cost rate function is formed considering replacement costand opportunity loss cost and deterioration dependent failure distribution, If the system has an increasingdeterioration dependent failure rate, the optimal deterioration level for preventive replacement can be determinedfrom minimizing the cost rate. An illustrative example is given for a Weibull deterioration dependent failuredistribution.