Evaluation of Deterioration of Concrete Due to Alkali-Aggregate Reaction Based on Through-the-Thickness Elastic Waves

Abstract

There are many reports related to concrete structures deteriorated by alkali-aggregate reaction (ASR). In order to evaluate the progress of deterioration, a visual inspection of the structure has been principally carried out. However, this visual inspection cannot detect internal defects of the concrete structure, so that sometimes the results of inspection mislead maintenance or asset management. Therefore, the evaluation method which can assess the internal damage should be established. Authors have studied wave velocity tomography as indices to evaluate inside concrete damage.

In this study, actual concrete bridge piers which have been damaged by ASR were experimented. Based on the velocity distribution namely tomogram, the internal defects of concrete affected by ASR could be visualized. Furthermore, the progress of deterioration could be evaluated by the resultant tomogram as well.