PO INFLUENCE OF THE TYPE OF MINERAL ADDITION IN BINARY AND TERNARY MIXTURES ON THE ECORR, RP, ICORR AND EIS OF CONCRETES EXPOSED TO AGGRESSIVE CONDITIONS CONTAINING CHLORIDES

Authors

Abstract

The focus of this paper is to determine the parameters of corrosion potential (Ecorr), polarization resistance (Rp) and electrochemical corrosion rate (Icorr) of concrete exposed to the aggressive condition, through weekly cycles of wetting in NaCl solution at 50 g/l and drying, for 300 days under the influence of the variables water/binder ratio - w/b (0.40 and 0.60) for better visualization of the corrosive phenomenon and the type of concrete (binary mixture of metakaolin in the content of 10% partial replacement by mass of cement, compared to reference concrete – without additions). In addition, for water/binder ratio - w/b of 0.60, the ternary mixture of silica fume and nanosilica was also evaluated. As a result, concretes with mineral additions showed higher Rp values and lower corrosion rates (less than 1.0 μA/cm²). The effect of the w/b ratio was significant for concretes without mineral additions and less important for concretes with mineral additions. In particular, the concrete without additions and a w/b ratio of 0.60 presented a significant corrosion value and a very low value of Rp (2.3 kΩ· cm²), denoting an intense corrosive phenomenon. Concretes with mineral additions showed Rp values between 13 and 21 kΩ· cm² and they remained in a range of active corrosion initiation.

Downloads

Download data is not yet available.

Published

2022-12-22

Issue

Section

Artigos