The structural integrity of many reinforced concrete structures can be broken due to corrosion of reinforcing steel. This phenomenon is quite pronounced in infrastructure where de-icing chemicals are widely used. The aim of this study is to examine the bond characteristics between reinforcing steel and surrounding concrete to evaluate its effect in corrosion. The strength of the bond was studied in terms of elongation load response, cracking behavior.It is shown that the friction between concrete and reinforcement along the edge of the rib prevents the concrete key from sliding relative to the rib. The force due to friction between the reinforcement and concrete at the rib is vectorially added to the cohesion component acting perpendicular to the rib. If friction between the concrete and reinforcement is lost, the only component of bond strength is the force acting perpendicular to the rib. In pullout failure, the friction between concrete and reinforcement is less important than in spalling failure.

Keywords: reinforcement, concrete, bond, slip, sliding, pullout, corrosion, concrete deformation.