In this thesis the field of supplementary cementitious materials (SCM) for so-called green concretes, and their influence on the properties of the hardened cement matrix and the corrosion of embedded steel, is discussed. Cements with such a modified composition achieve a greater economic effect due to better utilization of the raw materials and energy needed for their manufacture. During the performed investigations, the basic materials for the production of cement were first dried and mechanically treated. They were then mixed together in the selected proportions and ground into six different cements. After the specific surface area, density, chemical composition, and chlorides content in the cements had been determined, mortar samples for testing were prepared. After a curing period of twenty-eight days the flexural strength, compressive strength, and static modulus of elasticity of the test specimens were determined. They were then exposed to accelerated chloride induced corrosion, and electrochemical measurements were performed by means of three different methods for monitoring and detecting changes in the state of corrosion of steel in concrete. With potentiostatic method the corrosion current densities at increased potential were followed according to adopted standard method. With electrochemical impedance spectroscopy the corrosion activity in 22-week period on samples immersed into chloride solution and on samples that were cyclically exposed to wet and dry conditions was measured. The resistance to capillary absorption and the porosity of the samples were determined. After completion of the investigations, the samples were longitudinally split into two pieces, and a visual inspection of the reinforcement surface was carried out. The acid-soluble and water-soluble chloride contents were determined for the specimens investigated according to the third method. Finally, the suitability and reliability of the methods used for monitoring and detecting changes in the state of corrosion of steel in concrete, based on visual inspection and the results of electrochemical measurements, were assessed.
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