Effect of Chlorides on Reinforcing Steel Exposed to Simulated Concrete Solutions

Abstract

The behavior of steel in chloride-free and chloride-contaminated simulated concrete solutions was studied to observe the degradation of steel as a result of addition of chlorides. One of the simulated concrete solutions was a saturated calcium hydroxide (Ca[OH]2) solution while the other was a solution made up of 0.6 M potassium hydroxide (KOH) + 0.2 M sodium hydroxide (NaOH) + 0.001 M Ca(OH)2. Corrosion behavior of the steel was studied electrochemically, and changes in the steel surfaces were studied using scanning electron microscopy (SEM) and Auger electron spectroscopy (AES). Behavior was compared to that of reinforced concrete cylinders subjected to alternating wetting and drying in 3.5% sodium chloride (NaCl) solutions.