STUDY ON RUST DETECTION OF RC STRUCTURE BASED ON ELECTROMAGNETIC PULSED EDDY CURRENT

A set of rust detecting system for reinforced concrete was designed based on the electromagnetic pulsed eddy current (EPEC). The EPEC detecting test on the reinforced concrete specimens with different reinforcement diameters was performed. The finite element (FE) model was established. The results of the reinforcement position experiment show the Hall voltage peak value (HVPV) of the same lift-off value positively correlates with the reinforcement's diameter, and the HVPV declines fast with the increase of the lift-off value. The rust experiments results show that with the same lift-off value, the HVPV increases with the increase of the horizontal distance from the Hall sensor to the reinforcement in the specimen. When the Hall sensor is at the same position, the HVPV increases with the increase of the diameter of the reinforcement in the concrete. The Hall voltage (HV), the HVPV, and the time of pulse rising (TOPR) of the same specimen are greater in the rust-free point than in the rusted points. And the results of the numerical simulation verify the validity of the conclusions of the physical experiments. Our above study shows that the detecting method can locate the reinforcement in the concrete accurately and ascertain its diameter effectively. Furthermore, the detecting method can identify the rust region of the reinforcement swiftly and evaluate the rust degree rapidly.