We evaluate chronological change of the performance of countermeasure for ASR.

Evaluation of countermeasure for Alkali Silica Reaction (ASR)

ASR (alkali–silica reaction) is a phenomenon caused by the reactive minerals within the aggregate reacting to an alkaline solution within concrete, resulting in the formation of abnormal expansion and cracks in concrete. There are several concrete structures suffering from ASR among Honshu-Shikoku Bridge Expressway. We applied surface protection for these structures expecting 1) to prevent intrusion of water and 2) to expel moisture accumulate inside the structure. In order to evaluate chronological change of the performance of countermeasure, we are measuring the moisture content inside the concrete structures.

Cracks due to ASR
(cracks emphasized with black lines)

Measurement of interior moisture content