In situ measurement of conductivity and temperature during concrete curing using passive wireless sensors

In this paper a new low cost, wireless unpowered sensor will be discussed that is designed to monitor the conductivity of concrete, which may provide information on the ingress of chloride ions during the life of the structure. A method of extracting temperature information from a previously developed corrosion sensor will also be presented. During a recent test, both a wireless corrosion sensor and a wireless conductivity sensor were placed in concrete and monitored throughout the duration of the curing process. Analysis of the data shows it is possible to determine temperature information based on the corrosion sensor response, allowing wireless in-situ temperature monitoring of the concrete during the cure. Monitoring curing temperature using the same sensor which would later be used for long-term corrosion detection would help reduce the cost of such a monitoring system.

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