A numerical study of pitting corrosion in reinforced concrete structures

Abstract

In RC structures, rebar corrosion causes the cracking of the concrete cover and the deterioration of the bond between the two materials. In this paper, a numerical model is developed to investigate these two phenomena. The corrosion pit is modeled as a radial displacement representing the volume expansion of the rebar. A concrete damage plasticity model is used to simulate the damaging of the cover and a particular care is given to finely model the concrete-rebar interface using a normal and tangential contact law. The numerical results obtained in our work are validated with experimental and analytical results from the literature. The first main conclusion of our work is that the pit size impacts highly the cracks paths and influences the length of the tensile cracks in the concrete. The second main result consists in showing and exploring the relation between the accumulation of the rust in the corrosion pit and the deterioration of the bond between the rebar and the concrete cover. • A 2D finite element model of pitting corrosion of a reinforced concrete beam is developed. • The evolution of the corrosion pit and volume expansion of the rebar is studied. • The evolution of crack patterns and crack length in accordance with the corrosion level is investigated. • The deterioration of the bond strength is studied and linked to the damaging of the concrete cover.