In view of the lack of human resources and financial budget that will be needed to maintain and manage Japan's infrastructure in the future, many facilities might have to continue to be used beyond their initially designed period of use. While it is necessary to examine the long-term durability of concrete materials to address this issue, there is a concern that long-term exposure tests alone may be insufficient.

Deterioration acceleration testing is an existing method for estimating long-term durability. However, the usefulness of acceleration testing is yet to be determined, as it also requires some long-term exposure testing to define an appropriate acceleration rate, and it also remains unclear how differences between the testing environment and the actual environment affect the deterioration process.

Therefore, we believe the next reasonable step is to perform simulations based on the actual deterioration mechanism in order to accurately predict the long-term durability of concrete materials in the future. In this study, we observed cement compositions and changes in the concentration distribution of various ions in concrete materials, and obtained their phase constitution through geochemistry phase-equilibrium calculation (GEMS; D.Kulik, 2013), and created simulations that indicate the areas where the concrete materials would become vulnerable (reduction in strength).