The effect of crack patterns on the corrosion of steel reinforced SHCC

Abstract

Ingress Potential Indices (IPI) based on crack width distributions have recently been proposed for water permeation and chloride diffusion into cracked SHCC. Reasonable correlation between chloride content and the IPICl index has been reported, based on chloride profiles determined for multiply cracked R/SHCC beams. In these beams, significant concentration levels of chloride at the surface of embedded reinforcing steel bars were recorded, but low corrosion rates and steel bar damage in the form of mass loss and pitting area and depth. Thus, IPIs appear to be reasonable indices of actual chloride ingress, but not of actual corrosion rates and damage. This has been postulated to be due to an altered electrochemical process of dominantly micro-cell corrosion in finely cracked SHCC. In this contribution, the effect of crack patterns on the corrosion of steel reinforcement in SHCC is discussed. This paper also presents a postulation that three different zones exist where different types of corrosion take place. These zones are directly linked to the crack pattern. The final aim of this project is to create an index which can relate the crack patterns of steel reinforced SHCC to actual chloride-induced corrosion.