Abstract
In the present study, it is investigated to obtain fundamental information on internal cracks in reinforced concrete (RC) members and to evaluate existing structures, by using ultrasonic testing (UT) and acoustic emission (AE) method. In order to apply these to RC structures, small-sized specimens containing cracks were made. A crack width is controlled from 0.15 to 2.0mm. The cracks are evaluated by UT transmitted waveforms. The growth of tensile and shear cracks can be identified by AE parameters.
The results of the laboratory test are applied to a RC pier of a bridge in which cracks are detected. The transmission method can determine the width and the distribution of cracks in the pier. AE activities under live load are also measured in the pier. The types of the cracking can distinguish between tensile and shear mode by AE parameter analysis.
