Experimental evaluation of rebars corrosion in concrete

The proper evaluation of rebars corrosion rate in concrete can provide reliable data for the evalua-tion and modeling of the structural behavior. Electrochemical methods, used since the years ’70, are based on the perturbation of the free corrosion conditions by means of DC or AC current (or potential): the experience gained in the last decades shows that the most reliable method is the linear polarization resistance, based on small DC polarisation vs the free corrosion potential. Promising results have also been got by the measurement of concrete resistivity in carbonated concrete. AC methods have been largerly used in laboratory, while their application is limited on site. Accelerated corrosion test have been used to simulate in short time a significant reduction of the cross section: the limitations of these methods are briefly discussed