MODELING OF REDUCTION IN THE CROSS-SECTIONAL AREA OF STEEL REINFORCEMENT IN CONCRETE UNDER THE ACTION OF CORROSIVE ENVIRONMENT

Process of depassivation of steel in concrete under the action of chloride corrosive environment is considered. Method of durable testing of bended reinforced concrete structures during corrosive period is described. Results of experimental research in steel reinforcement corrosion in reinforced concrete beams under the action of corrosive environment are described in the article. The diagram of corrosive potential changes during the testing time is given in the article. Measurements of corrosion potential were carried out by the corrosion analyzing instrument. Analysis of corrosive potential changes during the testing time was carried out. Main properties and features of chloride corrosion process and damages are considered. Corrosive pits on the surface of the reinforcement bars were studied. Measurements of depth and diameter of the corrosive pits were carried out. Stress-strain diagrams of steel after the corrosive period were obtained. Mathematical model of reduction in the cross-sectional area of steel reinforcement in concrete under the action of corrosive chloride environment is suggested. This model allows to consider effect of concrete cover thickness on depth of corrosion. Comparison of experimental results and theoretical calculations reveals high accuracy of corrosion damage definition by given mathematical model. The ways to use the model are suggested. The given model allows to consider corrosive damages of steel rebars by definition of cross-section area losses and may be used in calculations of strength and deformations of RC structures. It’s possible to use the model for prediction of the remaining strength life of RC structures.

хлоридная коррозия, арматура, эксперимент, математическая модель, chloride corrosion, steel reinforcement, experiment, mathematical model

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