• Journal of the Korea institute for structural maintenance and inspection
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• v.27 no.2
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• pp.58-66
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• 2023

In this study, cable tension was measured using the vibration method, and a vision-based system was applied as a sensor to measure the displacement response of a cable in a non-contact method. In the vision-based system, the camera is installed in a location that considers the target structure and the field of view of the camera. However, it can be difficult to recognize the control points required to measure the displacement response of a structure as the target structure and other structures such as vehicles may be included in the image at the intended installation location. In this study, a distorted image including a vehicle shows inaccurate results in image analysis due to the installation position of the vision-based system. Accordingly, the image including the vehicle was eliminated by calculating the similarity between the two images. To verify the validity of the method of estimating the cable tension of cable-stayed bridges using the proposed method, the vibration method was applied to cable-stayed bridges in service to measure the tension.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2009.04a
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• pp.553-556
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• 2009

최근 우리나라의 건설 분야에서는 생애주기비용(Life Cycle Cost;이하 LCC)/가치공학(Value Engineering; 이하 VE)을 적용한 구조물 설계가 실시되고 있다. 이는, 건설교통부에서 공공건설사업의 효율성을 제고하기 위하여 실시하고 있으며, 대통령령에 따라 "건설기술관리법시행령"을 제정하여 공공사업분 수행 절차와 기준을 법제화 하였으며 이후 시행령 38조 13의 "설계의 경제성등 검토" 실시를 의무화하는 시행지침을 작성하여 수행하고 있다. 이러한, LCC/VE의 검토에서 보수 보강 공사비 산정은 유지보수공사 프로파일링을 통한 보수 보강 시기를 산정(건설교통부, 2003)하여 교량 구성요소별 보수 교체 주기를 산정(건설교통부, 2001)에서 제시한 기간을 적용하여 LCC/VE를 평가하고 있다. 하지만, 이러한 보수 보강 공사비의 적용은 일괄적인 적용이며, 예전 국내의 교량 건설기술이 현재와 같이 발전된 상태에서의 현황이 아니므로 본 연구에서는 현재 고속국도에 완공되어 운용중인 교량 구조물을 시설물의 안전관리에 관한 특별법 시행령(2008)에 따른 "시설물의 안전점검 및 정밀안전진단 지침"에 의한 교량의 초기점검, 정밀점검 및 정밀안전진단 자료를 조사 분석하여 보수 보강 공사비 곡선을 추정하려 한다.

• Journal of the Korea institute for structural maintenance and inspection
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• v.17 no.3
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• pp.97-107
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• 2013

Culverts are structures constructed across river levees. Since river levees are to be constructed continuously, constructions of culvert are known to reduce the stability of river levees. In order to establish an effective inspection system of culverts, a visual inspection system using checklists and smart phone was recommended in this paper. It was determined that the recommended visual inspection checklist is applicable in establishing the investment priority based on the culvert's repair plan establishment, repair and precision safety inspection.

• 한국지형공간정보학회:학술대회논문집
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• 2003.09a
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• pp.145-148
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• 2003

좁은 면적을 효율적으로 이용하고자 현대의 구조물들은 더욱 고층화 및 대형화가 되어가고 있는 추세이며, 이러한 구조물들에 대한 안정성 및 유지관리의 효율적인 자료관리가 시급한 실정이다. 또한, 구조물의 안정성에 관여된 여러 가지 요소들을 보다 종합적이며 효율적인 자료의 관리가 뒷받침이 되어야 보다 정확하고 경제적인 유지관리가 이루어질 것이다. 따라서, 본 연구에서는 구조물의 안전진단의 자료를 기초로 하여 효율적이며 조직적인 자료관리를 위하여 GIS를 적용하여 구조물의 유지관리 시스템 구축에 대한 효용성에 대하여 연구하였다.

• Proceedings of the Korean Society of Marine Engineers Conference
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• 2006.06a
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• pp.275-276
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• 2006

선박 및 해양기자재의 안전 진단을 위한 기존의 기술은 접 센서(point sensor)를 이용한 변형률 측정 기술이 대부분이라 할 수 있다. 본 논문은 기존의 기술보다 효율적으로 응용될 수 있는 광섬유 센서를 이용한 분포 개념의 온도 및 변형률 측정(DTSS: Distributed Temperature & Strain Sensing) 기술에 대해 소개하고 있다. 이 기술은 선체 응력 모니터링, 해양 구조물 안전진단, subsea flowline 모니터링, platform의 riser 안정성, umbilical 모니터링 등에 활용될 수 있다.

• Journal of the Korea institute for structural maintenance and inspection
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• v.16 no.6
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• pp.45-55
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• 2012

The road luminaires have been treated as subsidiary electric apparatuses in the road although they are indispensable facilities which people use the road safely. Because of this misunderstanding, there are not many researches on luminaire supports against the wind loads. Therefore, a typhoon has overturned or damaged many luminaire supports without having sufficient structural safeties. The purpose of this study is to review the current design criteria and to suggest the improvement of design methods based on the structural safety and compatible with the site conditions of luminaire supports. The stress concentration around the inspection hole, which causes the collapse of luminaire supports, is analyzed and stress reduction method is suggested with the improved design methods.

• Journal of the Korea institute for structural maintenance and inspection
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• v.27 no.6
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• pp.30-38
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• 2023

As the number of old buildings subject to safety inspection increases, the burden on designated institutions and management entities that are responsible for safety management is increasing. Accordingly, when selecting buildings subject to safety inspection, appropriate safety inspection standards and appropriate technology are essential. The current safety inspection standards for old buildings give low scores when it is difficult to confirm damage such as cracks in structural members due to finishing materials. This causes the evaluation results to be underestimated regardless of the actual safety status of the structure, resulting in an increase in the number of aging buildings subject to safety inspection. Accordingly, this study proposed a thermal imaging technique, a non-destructive and non-contact inspection, to detect cracks inside finishing materials. A concrete specimen was produced to observe cracks inside the finishing material using a thermal imaging camera, and thermal image data was measured by exciting a heat source on the concrete surface and cracked area. As a result of the measurement, it was confirmed that it was possible to observe cracks inside the finishing material with a width of 0.3mm, 0.5mm, and 0.7mm, but it was difficult to determine the cracks due to uneven temperature distribution due to surface peeling and peeling of the wallpaper. Accordingly, as a result of performing data analysis by deriving the amplitude and phase difference of the thermal image data, clear crack measurement was possible for 0.5mm and 0.7mm cracks. Based on this study, we hope to increase the efficiency of field application and analysis through the development of technology using big data-based deep learning in the diagnosis of internal crack damage in finishing materials.

• Journal of the Korea institute for structural maintenance and inspection
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• v.20 no.1
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• pp.118-125
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• 2016

This paper proposes the appropriate waterproofing methods for underground structures after applying different types of waterproofing materials on the concrete test specimens and selecting the best results out of humidity testing in winter conditions. Results of the testing showed that the underground structures absolutely require relevant waterproofing application based on the environmental conditions; when applied with interior waterproofing, the results showed that the concrete maintained high level of humidity and reinforcing steel within the concrete layer corroded. However, when applied with exterior waterproofing, it was shown that the waterproofing layer prevent direct contact with water and concrete, thereby protecting the concrete structure and improving overall durability. It follows that during underground structure construction, exterior waterproofing methods are have shown by an effective method for improving the durability as well as providing a comfortable interior environment for users.

• Journal of the Korea institute for structural maintenance and inspection
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• v.15 no.6
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• pp.147-155
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• 2011

The bridges where serious damages, defects, material degradations, etc. are not found can be presumed to have enough safety for the specified design loads, nevertheless, in many cases the loading carrying capacity is rated through loading tests. The safety specifications and manuals get no further than qualitative instructions for performing loading test or not. Some studies presented the improved appraisal methods for determining the load carrying capacity; however, the feasibility studies for loading test are scarcely carried out. This study examines an existing question, whether the loading tests are necessarily required in the safety assessment or not, and suggests an alternative for that via a statistical analysis for dozens of condition evaluation reports for concrete bridges.

• Journal of the Korea institute for structural maintenance and inspection
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• v.6 no.3
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• pp.185-192
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• 2002

Prototyping for field inspection safety assessment expert system of bridge structures is presented in this paper. Knowledgebase with production rules is constructed using the semiautomatic method on the basis of bridge inspection manuals and working reports of the related agency. Backward inference method is taken with the aids of external shells as a inference engine of knowledge-based systems. Implementation of the developed prototype system on MS Windows98 will shows inspiring aspects useful to guide and standardize the field works. In the case to be reinforced with abundant knowledge bases, this will be expected to be educate the practicing engineers.