The characteristic feature of fracture of steel reinforcement in ASR-deteriorated concrete structures

The brittle fracture of steel reinforcement caused by an excessive expansion of concrete due to the alkali-silica reaction (ASR) has recently been detected especially in large numbers of about 40 bridge piers in Japan. At present, concerning the rehabilitation of such severely deteriorated bridge piers with the fracture of steel reinforcement, their diagnosis and maintenance procedure has been a matter of concern for civil engineers. The author has engaged in the strengthening work of bridge piers on the Noto expressway in Ishikawa prefecture. This report introduces the recent survey on actual conditions of ASR-deteriorated bridge piers with the fracture of steel reinforcement and the counter measure applied to them.