Influence on Crack to Reinforcement Corrosion in Cast-in-place RC Structures Served under Chloride-Attack Environment

Abstract

Cracks generated in RC structure, especially served under the chloride-attack condition, promote the rapid reinforcement corrosion and lead to be dangerous in structural safety. The influence on existence and width of cracks to reinforcement corrosion concerned to chloride attack was investigated focusing to the cast-in-place RC structures served for long period as agricultural hydraulic facility. Intruded chloride ion concentrations showed different tendency due to the environmental condition, i.e., exposed to air or under the water. Slight reinforcement corrosion was confirmed even though there were no cracks and assured the cover thickness of reinforcement, however, most of them wasn't harmful corrosion. In case when the crack was generated in structure, degree of reinforcement corrosion was affected to the type of reinforcement, it was suggested that deformed bar was effective on durability of RC structure. The progress of reinforcement corrosion was influenced to not only the direction but also the locational relations of both crack and reinforcement. Chloride attack condition was so severe for RC structure, therefore, it was dangerous to utilize the allowable crack width configured for normal environment, necessary to configure the intrinsic crack width for chloride attack environment.