SURFACE TREATMENT EFFECTS ON THE CORROSION OFREINFORCED STEEL IN CONCRETE EXPOSED TO DRYCONDITION

The destroying of Tafel region in many cases is not due to complication u'ith mass transfer , but due to IR - drop effsct specially in dilute solutions ( i.e., of high resistivity) . Accordingly, the corrosion behavior of reinforcement in reinforced concrete was investigated using electro - chemical measurements. The work was carried out with small steel rods: cleaned and previously oxidized embedded in resistance Portland cement concrete cylinders exposed to dry conditions' In this investigation a theoretical model equation has been adopted including IR- drop term: AE =AEA +RAi = -bclogicorr.+ bclog/Ai/+R /Ai/ In order to determine corrosion paiameters of iystem investigated (i.e., icorr., bc, and Rc. A) equation above was based on the analysis of cathodic Polarization curve free from mass transf'er effect .It has been found that the corrosion curent of pre- oxidized steel is higher than the cleaned one , and this corrosion rate is concrete contaminant & time of exposure dependant. because of the importance of electrical resistance of concrete & its relationship to the corrosion rate of reinforcing steel. An attempt was made to find this resistance from the IR-drop term in the above mentioned equation.