Influence of long-term corrosion in chloride environment on mechanical behaviour of RC beam

The structural performance of a 27-year-old corroded beam was investigated. The cross-sectional area loss, load-carrying capacity, mid-span deflection and force–elongation of some of the corroded reinforcing steel bars were measured. It was found that the mechanical performance after 27 years of heavy corrosion was reduced in terms of both ultimate load and ductility but that ductility would be potentially the biggest problem for the requalification of corroded reinforced concrete members according to the prescriptions of standards. The experimental results revealed a more brittle failure mode of the corroded RC beam in comparison with the ductile failure mode of a control beam of the same age. This was linked to the change in mechanical properties of corroded steel bars in comparison with non-corroded bars.

► We have tested in 3-points bending, two 27 old beams: one corroded and one control.
► Corrosion results of natural process and then corresponds to in situ conditions.
► The loss of ductility of corroded beam is a major phenomena.
► Ultimate elongation of steel bar is highly reduced by corrosion.