The Effect of Corrosion and Load on Reinforcement Bond Strength

An experimental investigation into the effects of corrosion and load on reinforcement bond strength is reported. The main variables examined are level of corrosion, pre-load, cover depth, bar type (plain and deformed) and age. It was found that pre-loading the specimens during the corrosion process only affected deformed bar specimens with the greatest cover thickness. Corrosion was seen to enhance the bond strength of plain bars unless cracking and loss of confinement was severe. Unlike the plain bars corroded bond strengths of the deformed bar specimens were less than the non-corroded bond strengths at every level of corrosion tested. An impressed electric current was used to accelerate the corrosion process. Variation of current density was found to change the morphology of the corrosion products and, hence, bond behaviour.