Estimation of Local Strain Distribution of Shear-Compressive Failure Type Beam Using Digital Image Processing Technology

화상계측기법에 의한 전단압축파괴형 보의 국부변형률분포 추정

  • Kwon, Yong-Gil (Institute of Construction Technology, Chungbuk National University) ;
  • Han, Sang-Hoon (Dept. of Civil Engineering, Chungbuk National University) ;
  • Hong, Ki-Nam (Dept. of Civil Engineering, Chungbuk National University)
  • Published : 2009.04.30


The failure behavior of RC structure was exceedingly affected by the size and the local strain distribution of the failure zone due to the strain localization behavior on the tension softening materials. However, it is very difficult to quantify and assess the local strain occurring in the failure zone by the conventional test method. In this study, image processing technology, which is available to measure the strain up to the complete failure of RC structures, was used to estimate the local strain distribution and the size of failure zone. In order to verify the reliability and validity for the image processing technology, the strain transition acquired by the image processing technology was compared with strain values measured by the concrete gauge on the uniaxial compressive specimens. Based on the verification of image processing technology for the uniaxial compressive specimens, the size and the local strain distribution of the failure zone of deep beam was measured using the image processing technology. With the results of test, the principal tensile/compressive strain contours were drawn. Using the strain contours, the size of the failure zone and the local strain distribution on the failure of the deep beam was evaluated. The results of strain contour showed that image processing technology is available to assess the failure behavior of deep beam and obtain the local strain values on the domain of the post-peak failure comparatively.


  1. Nakamura, H. and Higai, T., Compressive Facture Energy and Fracture Zone Length of Concrete, Modeling of Inelastic Behavior of RC Structures under Seismic Loads, ASCE, 2001
  2. Bazant, Z. P. and Pijaudier-Cabot, G., ''''Nonlocal Continuum Damage, Localization Instability and Convergence,'''' J. Appl. Mech., Vol. 55, 1988, pp. 287-293.
  3. Bazant, Z. P. and Planas, J., Fracture and Size Effect in Concrete and Other Quas-Ibrittle Materials, CRC Press, 1998.
  4. 酒井理哉ほか, "畵像計測を利用した鐵筋コンクリ一トの ひずみ計測の試み," 土木學會第56回年次學術講演會, CS3-002, 2001, pp.164-165.
  5. 權庸吉ほか, "せん斷壓縮破壞するはりの局所ひずみ分布 と積分型非局所構成則の適用,"日本コンクリ一ト工學年次 論文集, 第28券第2 , 2006, pp. 775-780.
  6. 上田尙史ほか, "せん斷破壞を生じるRCはりおよび柱のエ ネルギ一吸收と破壞プロセス," 日本コンクリ一ト工學年次論文集,第26券第2 , 2004, pp.1003-1008.
  7. Lertsrisakulrat, T., Niwa, J., Yanagawa, A., and Matsuo, “Concepts of Localized Compressive Failure of Concrete in RC Deep Beams,” Journals of Japan Society of Civil Engineers(JSCE), No. 697, Vol. 54, 2002, pp. 215-225.