The effects of corrosion extend far beyond the obviously-effected durability of concrete structures and on to other properties, such as strength shear capacity and ductility. Take a look at the way that the author says corrosion can limit the ductility of a concrete structure:
Corrosion can significantly reduce the ductility of RC sections. This is critical in seismic design and evaluation. Corroded sections have lower ductility, which means their plastic deformation is limited. This will affect the seismic response of the elements. Corrosion of reinforcement in the lap splices will affect the load transfer in the laps, preventing the to develop yield stress.