Influence of corrosion on the friction characteristics of the steel/concrete interface

This paper reports results of an experimental programme to measure changes in friction characteristics of the interface between reinforcement and concrete as a result of the formation of corrosion products on the surface of the steel. The aim of the study was to determine whether a weak corrosion layer contributes to reported reductions in residual bond capacity. Corrosion was carried out under accelerated conditions using three different conditioning regimes. Principal parameters included in the investigation are conditioning regime, the amount of corrosion, and the stiffness of the restraint to expansion of the corrosion products.Experimental results indicate that corrosion products do not impair friction characteristics of a bar/concrete interface when surface crack width does not exceed 1.0 mm.