The distribution of hydration products at the steel-concrete interface for concretes subjected to electrochemical treatment

Abstract

Mortar specimens containing steel ribbon after electrochemical treatment, were manufactured to mimic the steel-concrete interface for microscopic analysis of SEM image containing the steel-concrete interface. The SEM image was quantified to determine the distribution of hydrations at the steel interface. As a result, it was found that electrochemical treatment increased the content of calcium hydroxide up to about 13%, imposing the passivity of steel. However, an increase in the current density resulted in increased porosity, presumably leading to a debondment in particular at the greatest current of 750 mA/m(2). After the treatment unhydrated cement grains increased by 2-3 times. (C) 2010 Elsevier Ltd. All rights reserved.