Rust distribution and corrosion-induced cracking patterns of corner-located rebar in concrete cover

In this work, the rust distribution patterns and concrete cover cracking behavior of corner-located rebar was studied by means of digital microscopy. The corner-located rebar with various cover thicknesses embedded in concrete specimens was exposed to artificial corrosive environments. The time-dependent evolution of rust distribution profiles around corroded rebar was measured and described by Gaussian models. The results show that for corner-located rebar, when the two side concrete cover thicknesses have the similar value, the onset of rust formation starts simultaneously and its rust pattern can be well described by two or three independent Gaussian functions. At the same level of corrosion, the cracking behavior of corner-located concrete can be considerably different, depending on the rust profiles and dimensional ratio of the two side concrete cover thicknesses.