Recently, people are concerned about how to maintain structure well because of safety. For effective maintenance of the structure, it should be resolved about carbonation, Durability, and Service Life issues. Solving that problem will Increase Safety of Structure. The carbonation velocity is produced an effect on carbon dioxide density of surrounding near structures, the concrete quality Therefore, This study compares the Velocity of carbonation due to maintenance of the structure. Also, this study will find Service Life of Concrete Structure through Predicting Carbonation Depth.