Abstract
In this study, the effect of rain exposure on the progress of reinforcement corrosion and state of cover concrete was investigated through a survey of actual concrete structures. Sample data on the carbonation depth, cover depth, and degree of rebar corrosion were collected from 221 locations, as well as the presence or absence of rain exposure at each sampling location, and the relationship between corrosion state, spalling or falling off of the cover concrete, and the degree of rain exposure were examined. The degree of rebar corrosion was determined by analysis of rebars obtained from actual structures.
It was found that, when there is exposure to rain, the change in moisture content is larger on the surface than inside the concrete due to repetitious wetting and drying at the surface. Consequently, the corrosion rate of rebar is larger at the concrete surface than further inside the concrete.
