atologia

Estudo de corrosão das armaduras frente ao ataque por cloretos e carbonatação em estruturas de concreto armado no laboratório de materiais de construção da Universidade Federal de Goiás

Cecília C. Bolina1, Danúbia A. Carvalho2, Danilo G. Martins3, Enio P. Figueiredo4, Mário Sérgio Jorge dos Santos5, Renata M.de Sá e Silva6, Tiago A. Couto7.

Abstract

The corrosion of steel reinforcement is one of the most critical problems of the structures of concrete and could severely undermine their security and ability to service. The main factors that cause the corrosion is the environment, which is embedded in the structure of concrete cover inadequate. Thus, the professional engineering, increasingly, have been concerned with the problem of corrosion of steel reinforcement of the structures of concrete. Among the main initiators of the process corrosive agents are carbonation of concrete and aggressive entry of ions such as chloride ions. This study aims to assess the overall effect of carbonation accelerated and the inclusion of 3% chloride ion in cement mass proportion the electrochemical properties of the steel reinforcement in concrete. The concrete specimens were made with cement CP II F-32, water/cement ratio was 0.7, with dimensions of the 20 x 30 x 6 cm, concrete cover of 2.5 cm and central armature of steel CA-50 to 10 mm in diameter. For the realization of electrochemical testing has been the use of the equipment GECOR 6, to measure corrosion potential (Ecorr), corrosion current (icorr) and ohmic resistance (Rohm). In the present paper, can be observed that the carbonation led to the record of the highest values of the icorr. For measures of Ecorr observed that in the samples with chlorides, they indicated that in the case of high levels of the ion, corrosion could be possible, even in an environment of low relative humidity, because of its effect hygroscopic. For the ohmic resistance it was found that it was mainly influenced by moisture contained