Primers to the Reinforcement in Mortars: Effectiveness as a Function of Primer Type, Exposure Conditions, and Amount of Sodium Chloride

Abstract

Abstract Primers are customarily used to prevent further corrosion of rebar during the repair process for corrosion-damaged concrete structures on the coast of Yucatan. However, there are not enough data about their effectiveness in this environment. This work presents laboratory data of mortar specimens where primers to the reinforcement were used as they are currently in localized repairs in tropical marine coasts. Four different, locally available primers were used according to their hypothetical protection mechanism (barrier, cathodic protection, inhibition, and repassivation). Primers were applied to the rebars and then embedded in mortar and subjected to two exposure conditions: partial immersion to different solutions of sodium chloride (NaCl; 0.4, 2.0, and 5.0%) and wet and dry cycles (12 h wet and 12 h dry) to a NaCl solution (3.5%) at 50°C. The electrochemical behavior of the specimens was followed through polarization resistance, corrosion potential, and electrical resistance. In practical term...