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

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/m2. After the treatment unhydrated cement grains increased by 2–3 times.