SH-SH stacked image
DETECTION OF FRACTURE PROCESS ZONE IN CONCRETE BY MEANS OF X-RAY W ITH CONTRAST M EDIUM
KOJI OTSUKA Department of Civil Engineering, Tohoku Gakuin University,
13-1, Chuo-1, Tagajo City, Miyagi Pref. 985 JAPAN
The purpose of the present investigation is to detect and to evaluate the fracture process zone of concrete by means of x-ray with contrast medium. The specimen used for this experiment is a rather compact tension test specimen. The contrast medium was filled in the small holes of the specimen during the loading and the x-ray exposing. Photographs and figures of fine cracks in concrete detected using this technique have been shown. Before the peak of the load, the start of fine cracks’ in concrete could be observed at the tip of the initial notch. As the crack opening displacement increased, developing fracture process zones were visualized. A correlation was obtained between the pattern of fracture process zone and the maximum size of aggregate.