Corrosion of rebar in concrete under cyclic freeze–thaw and Chloride salt action

• The coupled freeze–thaw and Chloride salt environments were considered.
• An ordinary concrete and a ternary-binder concrete were tested.
• Both the open circuit potential and Tafel potentiodynamic polarization measurements were conducted.
• Corrosion of rebar was depressed due to temperature effect and ice obstruction.

We studied the coupled effects of freeze–thaw (F–T) cycling and chloride on corrosion of rebar in concrete. An ordinary concrete and a ternary-binder concrete were immersed in 3.5 wt.% NaCl solution and endured up to 200 F–T cycles. We found: (1) the risk of corrosion of steel reinforcement in concrete remained in the “passive region”, even with increasing F–T cycling, although serious spalling occurred for all concrete specimens; (2) factors that reduce rebar corrosion include lower temperatures, non-wetting phase percolation which blocks harmful chloride penetration, and insufficient oxygen supply; and (3) blends do not seem to improve the resistance to reinforcement corrosion.