Journal of the Korean Geotechnical Society (한국지반공학회논문집)

Korean Geotechnical Society (한국지반공학회)
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An Optimal Digital Image Analysis Technique for Measuring Deformation of Granular Soils

사질토의 변형 측정을 위한 최적의 디지털 이미지 해석 기법

  • Received : 2009.10.22
  • Accepted : 2009.11.25
  • Published : 2009.12.31
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Abstract

To measure the soil deformation, two common techniques of the digital image analysis-Particle Image Velocimetry (PIV) and Digital Image Correlation (DIC)-have been used. To generally apply these techniques to the soils, the accuracy of these techniques should be evaluated under various conditions. In this study, the influence factors including the image resolution, the degree of displacement and deformation, the size of pixel subsets, and analysis techniques were analyzed. The deformation of an idealized particle assembly using the discrete element method was measured by the digital image analyses, and then the results were compared with the actual deformations. To conduct the optimal digital image analysis, various factors are systematically analyzed in terms of the degree of the displacement and the deformation.

흙의 변형을 측정하기 위해 적용되는 이미지 해석 기법으로는 Particle Image Velocimetry(PIV)와 Digital Image Correlation(DIC)가 있으며, 이 기법들이 더욱 널리 활용되기 위해서는 각 기법에 따라 다양한 조건에서 정밀도를 평가하는 연구가 필요하다. 본 연구에서는 이미지 해상도, 변위 및 변형 정도, 픽셀 집합의 크기 및 해석 기법의 다양한 요소를 고려하여 사질토의 변형을 관찰하기에 적합한 최적의 이미지 해석 기법을 제시하고자 한다. 개별요소법(DEM)을 이용하여 구성된 가상의 사질토 이미지를 활용하여 이미지 해석을 행하고 변위를 산정한 후, 개별 요소법의 변위와 비교하였다. 각 영향 요소들이 정확도에 미치는 영향을 분석하였고, 변위 및 변형 정도에 따라 최적의 이미지 해석조건을 제시할 수 있었다.

Keywords

References

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