한국건설순환자원학회논문집 (Journal of the Korean Recycled Construction Resources Institute)

한국건설순환자원학회 (Korean Recycled Construction Resources Institute)
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환경적 요인에 따른 비파괴 철근 탐사의 오차율에 관한 연구

A Study on the Error Rate of Non-destructive Rebar Detection Under Different Environmental Factors

  • 강범주 (경상국립대학교 토목공학과) ;
  • 김영환 (경상국립대학교 토목공학과) ;
  • 김영민 (국토안전관리원 정책연구실) ;
  • 박경한 (국토안전관리원 정책연구실) ;
  • 오홍섭 (경상국립대학교 토목공학과)
  • Kang, Beom-Ju (Department of Civil Engineering, Gyeongsang National University) ;
  • Kim, Young-Hwan (Department of Civil Engineering, Gyeongsang National University) ;
  • Kim, Young-Min (Korea Authority of Land & Infrastructure Safty) ;
  • Park, Kyung-Han (Korea Authority of Land & Infrastructure Safty) ;
  • Oh, Hong-Seob (Department of Civil Engineering, Gyeongsang National University)
  • 투고 : 2021.10.22
  • 심사 : 2021.11.06
  • 발행 : 2021.12.30
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초록

철근콘크리트 구조물의 내구성 및 안전성은 콘크리트의 균열 및 강도와 더불어 철근의 배근상태나 콘크리트 피복 두께에 크게 의존한다. 콘크리트 내에 매립되어 있는 철근 정보를 정확히 파악하는 방법엔 국부 파괴법과 비파괴 철근 탐사 시험이 있다. 일반적으로 부재 손상을 최소화하기 위해 비파괴 철근 탐사 시험을 통해 파악하며, 비파괴 철근 탐사 시험에는 전자파레이더법, 전자기유도법, 방사선법 등이 있다. 콘크리트의 함수율과 온도는 콘크리트의 전기적 특성인 유전율에 영향을 미쳐 비파괴 철근 탐사 시험 결과에 간섭을 방생시킨다. 따라서 본연구에서는 콘크리트의 표면수율과 온도에 따라 전자파레이더법과 전자기유도법이 받는 영향을 분석하였다. 장비와 기술의 발달로 원리와 상관없이 24℃ 시험체에서는 평균 오차율이 5% 이하로 나타났으며 특히 전자기유도법의 경우 매우 높은 정확성을 갖는 것을 확인하였다. 전자파레이더법은 습윤상태보다 건조상태에서 상대적으로 오차율이 작은 특성을 나타내었으며, 고온에서는 다소 높은 오차율이 나타났다. 탐사 대상의 온도가 낮고 건조한 경우 전자파레이더법을 적용하고, 탐사 대상이 습윤상태이거나 고온에서는 전자기유도법을 사용하여 오차를 감소시킬 수 있음이 확인되었다.

The durability and safety of reinforced concrete structures significantly depend on the reinforcement conditions, concrete cover thickness, cracks, and concrete strength. There are two ways to accurately determine the information on reinforcing bars embedded in concrete - the local destructive method and the non-destructive rebar detection test. In general, the non-destructive rebar detection tests, such as the electromagnetic wave radar method, electromagnetic induction method, and radiation method, are adopted to avoid damage to the structural elements. The moisture content and temperature of concrete affect the dielectric constant, which is the electrical property of concrete, and cause interference in the non-destructive rebar detection test results. Therefore, in this study, the effects of the electromagnetic wave radar method and electromagnetic induction method have been analyzed according to the temperature and surface moisture content of concrete. Due to the technological advancement and development of equipment, the average error rate was less than 5% in the specimens at 24℃, irrespective of their operating principles. Among the tested methods, the electromagnetic induction method showed very high accuracy. The electromagnetic wave radar method indicated a relatively small error rate in the dry state than in the wet state, and exhibited a relatively high error rate at high temperatures. It was confirmed that the error could be reduced by applying the electromagnetic wave radar method when the temperature of the probe was low and in a dry state, and by using the electromagnetic induction method when the probe was in a wet state or at a high temperature.

키워드

과제정보

본 연구는 국토교통부 시설물 점검 및 진단장비 검·인증을 위한 성능평가 기술개발(21CTAP-C153054-03)의 연구비 지원으로 수행되었습니다.

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