2014 Volume 63 Issue 7 Pages 438-442
Cathodic protection is applied to prevent AC corrosion and soil corrosion, which are generated in holiday of buried coated steel pipe. However, there is no way to measure the current density flowing into holiday, cathodic protection is managed as an index to earth surface potential or the current density of a probe buried near the steel pipe. We developed new method for estimating the alternating current density by non-digging. Also we showed the effectiveness of the method through the verification experiment. The proposed method is expected to be applied for cathodic protection management of buried steel pipe.