Novel sensor for non-destructive durability monitoring in reinforced concrete

Reinforced concrete is generally a durable material; however, it is also subjected to various degradation mechanisms, amongst them, corrosion of the reinforcing steel is the most common one. In this work, we present a novel sensor to be embedded in concrete and to monitor simultaneously the main parameters that lead to corrosion initiation, namely pH and chloride concentration. Instrumented mortar specimens were exposed to carbonation and chloride ingress and changes in pH and chloride concentration were continuously monitored. The results obtained show the need to monitor these two parameters simultaneously when assessing the corrosion risk and we believe the use of our sensor can strongly improve the decision-making in engineering practice.

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