Evaluating of the corrosion in concrete of beams reinforced in the presence drinkable water and with NaCl 3.5%

Abstract

The aim of this paper is the evaluation of  the behavior of corrosion in reinforced concrete beams, by means of electrochemical techniques corrosion potential measurements and Linear Polarization Resistance techniques. These beams are exposed to moisturizing and drying cycles with 3.5 % sodium chloride (NaCl) and drinkable water. Up to now, the Linear Polarization Resistance technique is the only that is applied for evaluating reinforced concrete structures and measuring the effect the reinforcement of corrosion and the deterioration mechanism of structures. The evaluation was affected in concrete of beams of 6” x 6” x 20”, reinforced with bars of 3/8” and stirrups of 1/4” to each 8”, which were divided in different areas protected with the purpose of having very defined the susceptible areas to suffer corrosion.They were carried out in three series, of six beams for each type of application: plain concrete, prexioded and preload, the theoretical permissible load that resist the proposal section is calculated with the formulas of the elastic theory, as well as a specimen witness, the corrosion potential, in most of the beams presented an uncertainty of the corrosion phenomenon for the sodium chloride (NaCl) according to the establish to the ASTM C876 standard and the corrosion rate of the beams exposed in sodium chloride presented a moderate corrosion degree.