- BUILDING STRUCTURES, BUILDINGS AND FACILITIES
- Calculated Dependencies For Predicting The Technical Condition Of Reinforced Concrete Structures
- UDC 620.193.013:620.197 DOI: 10.33622/0869-7019.2021.06.04-12

**Boris V. GUSEV**, e-mail: info-rae@mail.ru

Russian University of Transport, Obraztsova, 9, str. 9, Moscow 127994, Russian Federation

**Alexandr S. FAYVUSOVICH**, e-mail: Fajvusovich@mail.ru

International Academy of Engineering, Gazetnyy per., str. 4, Moscow 125009, Russian Federation

**Abstract**. A mathematical model of the processes of chloride and carbonate corrosion is constructed, which takes into account the mass transfer of the acid reagent in the capillaries of the longitudinal direction with the flow into the transverse ones. In the transverse capillaries, a neutralization reaction takes place with the formation of a mobile boundary of the phase transformation. A system of equations determining the concentration of reagents in the free and bound states is presented. The dependences characterizing the shape and movement of the corrosion front, behind which there is a completely neutralized layer with a flat interface between them, are obtained. The dependences for predicting the technical condition of structures under conditions of carbonate and chloride corrosion are given. The initial data for forecasting is provided to be determined on the basis of data on the distribution of concentrations of the aggressive component in the bound state, and general data - in the operated structures. The proposed method for determining the generalized parameters based on the data of the concentration distribution over the depth of the layer of the operated structures provides increased prediction accuracy.

**Key words**: carbonate and chloride corrosion, reinforced concrete structures, phase transformations, corrosion front, mathematical model, forecasting, generalized parameters. - REFERENCES

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