Steel Microstructure and Compressive Strength in Mortar When an Electrochemical Chloride Extraction is Applied

Author(s): Citlalli Gaona-Tiburcio, S. Rodríguez, L. Hernández, O. Guarneros, A. Cárdenas

The focus of this paper is to examine and review how applications of Electrochemical Chloride Extraction (ECE) affect the mortar mechanical properties. The mortar specimens were prepared with water/cement (w/c) ratio of 0.5 and contaminated with 5% of NaCl by mass of cement. A clean steel rod was centrally embedded in each specimen. The electrochemical treatments were based on different electrical current densities of 1, 3, 6 and 9 A/m2 that were applied for 15 days. The state of corrosion was monitored before, during and after applying ECE regularly for two weeks. Selected samples from the cover zone of the untreated and treated specimens were taken to assess their chloride profiles. Despite being a slight change in the microstructure at the surface of the steel rod when this technique was applied (high current densities), the results of the compressive strength on mortars were not affected by ECE.

Corrosion, Chloride, Mortar, Microstructure, Compressive Strength

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