Original Paper(Vol.62 No.11 pp.702-709)

Proposal of Pre-Detection Method for Crack Occurrence in Corroded Reinforced Concrete Beam by Digital Image Correlation

Yoshihiko TSUKUDA, Shinichi MIYAZATO and Michio UNEDA

Abstract: Reinforced concrete (RC) structures deteriorate because of the penetration of chloride ions into the cracks in concrete. Therefore, highly accurate detection of cracks is important. In this study, a pre-detection method for crack occurrence during RC beam bending is developed. The strain on a concrete surface is measured by a digital image correlation method. In addition, a method for detecting crack initiation is developed. In particular, RC beams used in experiments are set in the crack propagation stage based on the actual condition of existing structures. As a result, the location of crack occurrence is detected beforehand by a map of strain with 600ƒÊ or above. Hence, an effective pre-detection method for crack occurrence has been proposed for RC beams in the crack propagation stage.

Key Words:Digital image correlation, Strain distribution, Crack detection, RC beam, Propagation stage