Abstract
This study aims at investigating the influences of local environmental conditions on the degree of damage in existing ASR damaged concrete structures and proposing a method for predicting the progress of ASR damages in future on the basis of the data obtained in the investigations. The ASR damages in the structures were found to rapidly proceed after the freezing-thawing repetitions due to changes in climate started to increase. It was also found from these investigations that the degree of deterioration in concretes depended on the local environmental conditions such as temperature, humidity and the supply of water from the outside. The combination of the alkalinity of pore solutions extracted from damaged concrete structures and the expansion of concrete cores from the structures by the use of the NBRI test was useful for predicting the progress of ASR damages in concrete structures.