Multiple data on the examination of concrete structures indicate that under the influence of various factors (temperature, humidity, gaseous medium) carrying capacity and rigidity during operation are reduced. The problems of assessing the residual life and durability of concrete structures are considered in the article. Experimental studies on the interaction of the concrete samples with aggressive sulfate medium are conducted. By measuring the micro-hardness, isochrones of degradations, enabling experiments to determine the rate of advance of the destruction front deep into the product; intensity changes in the durability properties of the material surface and other features which characterize the degradation process were obtained. The article investigates the mechanisms of corrosion processes in reinforced concrete in condition of sulfate corrosion. The paper proposes the calculation model and the method that predict the durability of concrete structures.