The compressive strengths of concrete in old drainage structures were measured by core test and non-destructive testing, and the neutralization depths were estimated. There are a high correlation between the core and non-destructive testing compressive strength and the carbonation depth.

All bridges are inevitably undergoing deterioration over time. Therefore, it is necessary to predict the maintenance control and to properly manage the maintenance control cost by deriving the appropriate repair and reinforcement timing. The deterioration of bridges appears to vary according to the years of use of bridges and the exposed environment. In this study, the correlation between the deterioration factor of the winter season and the damage rate of the bridge deck was derived from 1117 total bridge data collected through the GPR(Ground Penetration Radar) system.

The map crack occurred in the concrete barrier and this crack is caused by the Alkali—Silica Reaction. As a result of the collision analysis according to the damage of the barrier, the barrier was found to be below the reference of structural performance when the crack height was 50cm or more. In the case, improvement is considered necessary.

교량 바닥판은 대형 차량 및 제설제와 같은 다양한 환경 요인으로 인해 급속히 악화되는 부재이다. 한국에 건설된 교량의 수명이 길 어짐에 따라 교량 바닥판의 교체 수요가 증가 할 것으로 예상된다. 다른 국가에서는 프리 캐스트 바닥판을 이용한 급속 교량 건설 기술이 열화 된 교량 바닥판의 교체 수요 대응을 위해 적극적으로 사용되고 있다. 본 연구에서는 국내 교량 바닥판의 상태평가 데이터를 수집 및 분석하여 교량 바닥판 열화 모델을 제안 하였다. 또한 교량 규모의 관점에서 열화된 교량 바닥판의 미래 대체 수요를 예측하였다.

회백색 응회암으로 구성된 경주 골굴암 마애불의 효과적인 보존처리를 위하여 구성암석의 특 징과 보존처리제 적용에 따른 효과를 살펴보았다. 구성암석은 팽윤성 광물인 몬모릴로나이트를 3-5% 함유하고 있으며, 물과 반응 후 팽윤성 광물의 층간간격이 증가함을 보였다(1.54-2.69%). 에틸실리케 이트 암석강화제를 적용한 후 시편의 표면 경도, 흡수율, 공극률 등의 물성은 향상되었으나 팽윤성 광 물의 층간간격이 감소하였으며(4.23-12.12%), 팽윤성 광물의 함량이 많을수록 그 정도는 컸다. 팽윤저 지제를 선 처리한 후 강화제를 적용하였을 때 물성은 강화제만을 처리하였을 때와 거의 유사한 결과 를 보였다. 팽윤저지제만의 처리로는 팽윤성 광물의 층간간격이 거의 변화되지 않았으며, 팽윤저지제 처리 후 강화제를 처리하였을 때는 XRD 패턴에서 팽윤성 광물의 세기는 줄어들었으나 층간간격의 변화는 강화제만을 처리하였을 때와 유사하여 팽윤저지제의 효과는 거의 없었다(4.10-11.85%). 따라 서 팽윤성 광물을 함유하고 있는 골굴암 마애불 구성암석을 강화시키기 위한 보존처리제로서 에틸실 리케이트 계열의 암석강화제는 적절치 않으며 이를 보완하기 위해 사용한 팽윤저지제도 효과적이지 못하다. 우수의 접촉으로 구성광물이 팽윤되어 풍화가 급속히 진행되기 때문에 현재로서는 하부와 측 면 등 풍화가 심한 부분에 우수접촉을 저지시키는 조치가 필요하다.

This paper presents an experimental study to evaluate complex deterioration resistances of concretes according to addition of modified sulfur. The complex deterioration tests were performed to concretes with freezing-thawing and deicing chemicals. From the test result, it was confirmed that the complex deterioration resistances of modified sulfur cement concrete was higher than that of normal concrete.

Domestic infrastructure facilities were built intensively in the 1970s and 1990s, and the resources required for maintenance and repair will increase sharply within the next 20 years. ‘A Comparative Study on the Classification and Financial Size of SOC(2012)’ showed that the size of the domestic infrastructure facility is shrinking. In this study, we investigated the case of asset management research and analyzed the trend of the aging of the domestic infrastructure. And then we present the direction of future research.

Visual inspection has generally been applied to examine the coating deterioration. However, it was difficult to evaluate an anti-corrosion performance of paint film. In this study, thus, to quantitatively evaluate an anti-corrosion performance of paint film under various corrosion enviornent, change in the impedance paint coating was evauated using EIS (Electrochemical Impedance Spectroscopy).

This paper presents an experimental study to evaluate complex deterioration resistances of concretes according to addition of modified sulfur. The complex deterioration tests were performed to concretes with freezing-thawing and deicing chemicals. From the test result, it was confirmed that the complex deterioration resistances of modified sulfur cement concrete was higher than that of normal concrete.

Domestic infrastructure facilities were built intensively in the 1970s and 1990s, and the resources required for maintenance and repair will increase sharply within the next 20 years. ‘A Comparative Study on the Classification and Financial Size of SOC(2012)’ showed that the size of the domestic infrastructure facility is shrinking. In this study, we investigated the case of asset management research and analyzed the trend of the aging of the domestic infrastructure. And then we present the direction of future research.

Visual inspection has generally been applied to examine the coating deterioration. However, it was difficult to evaluate an anti-corrosion performance of paint film. In this study, thus, to quantitatively evaluate an anti-corrosion performance of paint film under various corrosion enviornent, change in the impedance paint coating was evauated using EIS (Electrochemical Impedance Spectroscopy).

The maintenance costs will be increased due to the aging of the bridge. Most of maintenance activity is generally known for preventing and repairing the deterioration by de-icing salts. The objective of this research is to investigate the minimizing strategy of maintenance costs for the deterioration by de-icing slats of highway bridges.

Recently, interests for maintenance of transmission tower are increasing to extend life of structures and reduce maintenance cost. However, existing classical diagnosis method of corrosion deteriorated degree on the transmission tower steel members, visual inspection, has a problem that error often due to difference of inspector’s individual knowledge and experience. In order to solve the problem, this study carried out to develop the corrosion deterioration inspection tool for transmission tower steel members. This tool is composed of camera equipment and computer-aided diagnosis system. We standardized the photographing method by camera equipment to obtain suitable pictures for image processing. Diagnosis system was designed to evaluate automatically degree of corrosion deterioration for member of transmission tower on the basis of the RGB color image processing techniques. It is anticipated that developed the corrosion deterioration inspection tool will be very helpful in decision of optimal maintenance time for transmission tower corrosion.

This study was carried out to systematically maintain and manage the trails by assessing the physical characteristics, the types of deterioration and impact rating class of trails located in Mt. Nam District of the Gyeongju National Park. The major trails followed 6 routes including Sambulsa-Geumobong(A), Yongjangsaji-Geumobong(B), Yongjanggol-Yiyoungjae- Gowibong(C), Cheonusa-Gowibong(D), Sangseojang-Forest road(E) and Tongiljeon-Forest road(F). The routes length of A was 2.2 km, 2.7 km of B, 3.4 km of C, 1.3 km of D, 2.0 km of E and 1.0 km of F. In the physical characteristics, A was the widest and F was the narrowest in the width and bared width of trail. In depth of erosion, B was the deepest and E was the shallowest. D was the steepest and E was the gentlest in the slope. In the results of analysing the types of deterioration, A were 13 types, 11 types of B, C and D, 10 types of E and 6 types of F. The times of appearance of deterioration types in A were 86 times, 75 times of B, 105 times of C, 48 times of D, 47 times of E and 13 times of F. In case of the impact rating class, trail erosion was Ⅱ degree, Ⅰ degree of trail expansion, root exposure, trail divergence and rock exposure.

This study was performed to analyze the importances review on deterioration items of concrete retaining wall using statiscal analysis. As a result of study, the main deterioration items of concrete retaining wall were found out and the results can be utilized for the efficient management.

This study was performed to analyze the deterioration items of jointed rock slope using the Precision Inspection Results. As a result of study, the deterioration items of jointed rock slope was found out. The results can be utilized for the efficient management.

Recently, the concern on the deterioration of concrete due to de-icing salts and its counter measurements has been increased. This paper discusses the results from investigation of pre-mature deteriorated existing road-subsidiary concrete structures and the specification of concrete quality.

Recently, the concern on the deterioration of concrete due to de-icing salts and its counter measurements has been increased. This paper discusses the results from investigation of pre-mature deteriorated existing road-subsidiary concrete structures and the specification of concrete quality.

This study, depending on the concrete mix material by performing the test on the basis of the wet and dry condition and freeze-thaw, and to elucidate the difference in the corrosion initiation time of there steel, in both environments, it is an object of correlation coefficient derived through the results of the accelerated corrosion test in a laboratory corrosion period of the structure of the marine environment.

Bridge decks are rapidly deteriorated by various environmental effects such as heavy vehicle and deicing salt, etc. For bridge owners in Korea, therefore, it is important to understand the defect characteristics and causes of deterioration of bridge decks as well as to predict the future need for bridge deck replacement based on proper deterioration models. Finding a solution to the problem, in this research, the site investigation for 76 domestic old bridges were undertaken and deterioration models of bridge decks were proposed by analysing service year-condition index relationships of more than 500 bridges.