Modelling of concrete cover cracking due to non-uniform corrosion of reinforcing steel

Abstract

This paper addresses the modelling of non-uniform corrosion in reinforced concrete. An uneven distribution of rust around the perimeter of the rebar is considered which represents the most common situation in real concrete structures and, especially, when they are exposed to a chloride environment. A comparison with the conventional approach based on a uniform corrosion and expansion pressure around the rebar is performed in both cracking pressure and cracking radial displacement terms. As a result, surface cracking appears much earlier in the case of non-uniform corrosion with corresponding vertical surface displacements being rather higher, with such an effect becoming more evident as cover increases. Finally, distinct cracking patterns are derived through the proposed embedded cohesive crack model by means of a practical example.