The aim of this thesis was to perform a critical comparison of a number of different electrochemical and physical methods for the monitoring of steel corrosion in concrete. Initially, some tests were performed on medium-sized reinforced-concrete columns located in a natural marine environment, into which electrical resistance probes were embedded. Electrochemical noise was measured using a\ud
five-electrode assembly, and corrosion potentials and rates were determined by the galvanostatic pulse technique. Since the results obtained in the case of these in situ measurements proved to be relatively unreliable, further research was performed in the laboratory on small-scale test specimens using electrical impedance spectroscopy in addition to the previously described test methods. The small size of the specimens made it possible to also perform X-ray micro tomography analysis, which proved to\ud
be highly important for our research results. These laboratory measurements were performed on different types of steel, which were embedded in carbonated mortar. The specimens were cyclically wetted with distilled water or a 3.5 % NaCl solution. The most reliable method for corrosion\ud
monitoring proved to be a coupled multi-electrode array. However, this method is difficult to install in actual structures, and a large amount of recorded data has to be processed. Good results were also obtained on similar test specimens using a simpler method with electrical resistance probes, which, however, has some disadvantages in chloride environments at high corrosion rates. The galvanostatic\ud
pulse technique, which is one of the most commonly used techniques for in situ corrosion monitoring, proved, on the basis of these laboratory tests, to be less reliable in the case of chloride contaminated concrete or mortar. On the other hand, X-ray computed micro-tomography turned out to be an extremely reliable non-destructive laboratory technique for the detection of corrosion type and the\ud
extent of corrosion damage. This technique was therefore used to evaluate the accuracy of the other used methods
