The goal of this investigation was to determine the effect of steel bar corrosion of reinforced concrete beams on the vibration frequency response. Simply supported concrete beams, with a rectangular transversal section and central zone contaminated with chlorides, were used in this investigation. The corrosion process was induced by adding table salt during concrete mixing, and further accelerated by impressing an anodic current to the steel reinforcement bar. During the corrosion-induced process, the beams were tested in flexure by applying a gradual load at the middle of each beam to deterlnine flexural stiffness. In addition, impact load testing was performed to determine the vibration parameters registered through several accelerometers placed on the beam. Natural frequencies were obtained from processing time history acceleration data. Both, loading-unloading and the vibration tests, were performed periodically until the target rebar radius loss due to corrosion was achieved. Preliminary results show a clear tendency in which the stiffness parameter EI decreases, and the natural frequencies shifts towards lower values as the corrosion of the embedded steel increases.
Key words: Corrosion, Concrete Cracking, Durability, Natural Frequency, NDT, Reinforced Concrete, Vibration Measurements