In the present paper a simple approach to model the effects of corrosion on bond between plain bar reinforcement and concrete with the finite element method (FE method) is shown. With the combination of a non-linear FE-solver and a discrete bond model it is sufficient to simulate corrosion by radial expansion of a concrete cylinder. The bond model used accounts for the effects of confinement and stresses in the vicinity of the reinforcement bar. Hence the effects of corrosion could be investigated with this simple approach. The model is calibrated on pull-out tests with RILEM specimen. Calculations conducted on beam end specimen containing plain surface bars show a plausible agreement with test results and with results known from literature.