Bond capacity of severely corroded bars with corroded stirrups

Abstract

Eccentric pull-out tests were carried out to study the influence of severe corrosion leading to extensive cover cracking, and the effect of corroded and non-corroded stirrups on the anchorage of deformed bars. The specimens were subjected to a low-rate electrochemical corrosion process for three time spans that caused a rebar weight loss up to approximately 20% in the main bars and 35% in the stirrups. Pull-out tests were then carried out in each specimen, on either the two corner bars or the middle bar, to measure the bond capacity. The effects of corrosion and the mechanical testing were simulated with non-linear finite-element analysis. The combination of tests and analyses gives a better understanding of the effect of high corrosion penetrations and the presence of corroded stirrups on failure modes. The presence of stirrups, corroded and non-corroded, was found to significantly change the behaviour of an anchorage region, namely the corrosion-induced crack pattern, the failure mode and the bond capacity.