Application of Detection Technique of Reinforcing Steel Corrosion in Concrete Using AC Impedance Method to Specimens Exposed at Seashores for Seven Years

摘要

The applicability of non-destructive corrosion detection using AC impedance method to the specimens is investigated, in which test specimens have been exposed to seashore environment for seven years at three different sites, Matsumae in Hokkaido, Nagoya and Ishikawa in Okinawa. The followings are main conclusions derived from the tests results: a) Steel corrosion in concrete and cracks in concrete cover due to steel corrosion were observed after seven years exposure. Steels in the specimens exposed to tidal condition in Nagoya corroded considerably. On the other hand, steels in the specimens exposed to seaside area in Matsumae and Okinawa corroded a little. b) The corrosion detection technique using AC impedance method can be well used to estimate amounts of steel corrosion of specimens irrespective of environmental conditions.