In construction practice of reinforced concrete with half-precast concrete members, it is important to inspect a bonding surface between half-precast concrete and cast-in-place concrete. The purpose of this study is to find the non-destructive inspection method that can find an internal defect in a bonding surface. In reference to actual reinforced concrete with half-precast concrete members, several types of concrete specimens which included voids and non-adhesion areas inside were made. The voids and non-adhesion areas inside specimens were explored using ultrasonic waves and electromagnetic waves in the experiment.
