In this paper we study the electrochemical response by techniques corrosion potential, linear polarization resistance and electrochemical impedance spectroscopy, to the mortars obtained with steel slag activated with sodium silicate, were subjected initially exposed to the accelerated carbonation and then immersed in NaCl solution to study the influence of carbonation on penetration of chloride ion, mixing these two corrosive phenomena of the same material. Afterwards the entry of each of the corrosive phenomena that occur in the steel, cathodic protection systems are used to protect steel. The efficiency of cathodic protection was determined; and it concludes that it is a rehabilitation technique able to stop corrosion in concrete structures carbonated alternatives and contaminated with chlorides, with a high degree of degradation in the structure.