Affordable Access

Influence of corrosion of reinforcing bars on the bond between steel and concrete

McGill University
Publication Date
  • Engineering
  • Civil.
  • Chemistry


Tension tests have been carried out for a preliminary study of the influence of the steel reinforcement corrosion on bond behaviour. The bond strength was studied through both transverse and longitudinal splitting cracks and a relative bond effectiveness of the corroded bars was determined from the crack spacing. Different stages of the corrosion were established to study their relative bond behaviour, ranging from no corrosion to complete corrosion at the steel-concrete interface. These stages have been achieved by using an accelerated corrosion method. An electrochemical method was used to accelerate corrosion within the specimens. Direct current was applied for increasing periods of time to the reinforcing bar embedded in the tension specimens, immersed in a concentrated sodium chloride solution (5% NaCl). The reinforcing bar served as anode, while a steel bar in water served as the cathode. The chloride content of the concrete plays an important role in the rate of corrosion. Chloride content was obtained for each tension specimen using the Volhard Method. Bond strength decreases rapidly with an increase in the corrosion level, especially in the case of any severe localized corrosion. It has been found that the first level of corrosion, which is 4 percent weight loss due to corrosion, resulted in a 9 percent decrease of nominal bond stress, while the sixth level of corrosion, with a 17.5 percent weight loss, resulted in a 92 percent weight loss of nominal bond stress. Bond behaviour is influenced by deterioration of the reinforcing bar ribs, and by reduced adhesion and cohesion of the reinforcing bar due to widening of the longitudinal splitting crack resulting from corrosion. (Abstract shortened by UMI.)

There are no comments yet on this publication. Be the first to share your thoughts.