Monitoring system for chloride content in concrete cover using electromagnetic wave and impedance methods

Reinforcement corrosion caused by the presence of chloride ions in the neighborhood of the re-bars has been identified as one of the major causes of deterioration of concrete structures. The chlorides could find their way to concrete either as part of constituent materials when sea sand is used, or, by gradual permeation and diffusion as in the case of marine structures, or, cases where deicing salts are used to melt away snow on highways, etc. Thus, determination of chloride content in a concrete structure is an important part of periodic nondestructive testing carried out for structures identified to be vulnerable to chloride induced reinforcement corrosion. In this report, the applicable monitoring system which is possible to estimate the distribution of chloride content included in cover concrete in the existing structures using electromagnetic wave method and impedance method which are non-destructive testing is reported.