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A Study on Concrete Efflorescence Assessment using Hyperspectral Camera

초분광 카메라를 이용한 콘크리트 백화 평가에 관한 연구

  • Kim, Byunghyun (Department of Civil Engineering, University of Seoul) ;
  • Kim, Daemyung (Department of Civil Engineering, University of Seoul) ;
  • Cho, Soojin (Department of Civil Engineering, University of Seoul)
  • 김병현 (서울시립대학교 토목공학과) ;
  • 김대명 (서울시립대학교 토목공학과) ;
  • 조수진 (서울시립대학교 토목공학과)
  • Received : 2017.10.17
  • Accepted : 2017.11.06
  • Published : 2017.12.31

Abstract

In Korea, the guideline for the bridge safety inspection requests to assess surface degradation, including crack, efflorescence, spalling, and so on, for the rating of concrete bridges. Currently, the assessment of efflorescence is performed based on the visual inspection of expertized engineers, which may result in subjective inspection result. In this study, a novel method using a hyperspectral camera is proposed for objective and accurate assessment of concrete efflorescence. The hyperspectral camera acquires the light intensity for a number of continuous spectral bands of light for each pixel in an image, which makes the hyperspectral imaging technique provides more detailed information than a color camera that collects intensity for only three bands corresponding to RGB (red, green, and blue) colors. A stepwise assessment algorithm is proposed based on the spectral features to decompose efflorescence area from the inspected concrete area. The algorithm is tested in the laboratory test using two concrete specimens, one of which is dark colored with efflorescence on a surface while the other is bright concrete without efflorescence. The test shows high accuracy and applicability of the proposed efflorescence assessment using a hyperspectral camera.

Keywords

References

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