An integrated probe for monitoring the corrosion of steel in concrete has been designed, fabricated and tested in a range of aggressive, chloride containing, concrete environments. The probe measures the variation with time of corrosion current, corrosion potential, concrete resistivity and temperature. The corrosion current is generated by a mild steel/stainless steel galvanic couple and measured using a zero resistance ammeter. The corrosion potential is measured by in-situ reference electrodes. The concrete resistance is monitored by measuring the resistance between segmented electrodes at a known spacing and the temperature is measured by a thermocouple incorporated in the probe. Seven probes were monitored over approximately four months in a range of concretes of different cement to aggregate ratios and chloride levels, and the results of the experiments given. The current drawn by the central anode for a range of concrete resistivities and cathode lengths was modelled using finite element analysis to investigate the effect of using a finite length of probe to model an essentially infinite reinforcement network. The results from the monitoring and mathematical modelling are presented and discussed. Finally suggestions for further development of the probe and automation of the probe logging equipment into a modular form suitable for general laboratory and field use are made.

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