Experimental investigation on the short-term impact of temperature and moisture on reinforcement corrosion

•Reinforced specimens at different relative humidities and temperatures were studied.•Passive reinforcement bars were not affected by variations in temperature and relative humidity.•Active reinforcement showed a temperature dependent behaviour.•Temperature dependency could be described by the Arrhenius equation. Moisture dependent activation energy was found.

In this study, reinforced concrete specimens with and without mixed-in chlorides were conditioned at different relative humidities and subsequently subjected to varying temperatures. Results of the study confirmed that neither temperature nor moisture content have a major impact on the corrosion state and rate of passively corroding reinforcement. For actively corroding reinforcement, a temperature and moisture dependent corrosion rate was observed. The temperature dependency could be described by the Arrhenius equation with moisture dependent activation energies of approximately 10 kJ/mol at 75% RH and 35–40 kJ/mol above 85% RH.