Abstract
As a detailed inspection of a concrete structure in service, core samples are usually drilled out and then physical properties are measured. In this study, damage estimation of concrete-core samples from structural concrete is developed, applying elastic wave method and X-ray computed tomography method. Concrete-core samples taken from reinforced concrete of an existing canal were tested. These samples are strongly influenced by freezing and thawing process. The crack distributions of concrete-core samples were inspected with helical CT scans, which were undertaken at one-millimeter intervals. After helical CT scan, damage of freeze-thawed samples was evaluated, based on elastic wave parameter. It is confirmed that the development of actual cracks in core samples were decreased in CT number and elastic wave velocity. In low CT number’s portion, the elastic wave parameter is decreasing compared to non-cracked portion. These results suggest that the decrease in physical properties could be evaluated by comparing average CT number with elastic wave properties in core test. These values are affected by the internal actual cracks. Thus, the damage of freeze-thawed concrete in service structures could be quantitatively evaluated by elastic wave method and X-ray computed tomography method.
