Verification on recovery performance of repaired reinforcement bar which corrode in the cracked concrete using neutron technology

The authors accurately measured the stress distribution of reinforcing bars of concretes using an engineering material diffractometer. Samples were taken from healthy reinforcing bar and corroded reinforcing bar in RC, and corroded reinforcing bar in RC where corrosion cracks had been repaired. They confirmed crack distribution inside the test specimens and the state of filling of the repair material through CT imaging using an imaging device. These techniques have been considered difficult until now, As a result of the verification, it was possible to capture the change in the adhesion stress distribution depending on the corrosion grade. It was also confirmed that when a repair material was applied to the corrosion cracks, the adhesion was restored by improving the frictional force and restoring the confinement effect of the concrete. (A.O.)