The algorithm of the simulation model implementation and the simulation results

   The article is devoted to the issues of forecasting the durability and reliability of reinforced concrete superstructures of bridge structures. It is assumed that the durability and reliability of superstructures depend on the condition of the main beams, the performance of which is determined by the condition of concrete and reinforcement. The purpose of the study is to develop a methodological approach to the study of reliability indicators of superstructure beams using simulation modeling methods.
   To study durability and reliability, to identify patterns of influence of stochastic parameters of traffic flow, maintenance technologies and operating conditions on the condition of bridge structures, simulation algorithms and procedures for ‘process-event’ generation of destructive factors are proposed. The reliability and durability of superstructure beams are determined by changes in the cross-sectional area of the reinforcement, considering the combined effect on concrete and reinforcement of the composition and intensity of traffic, technological processes of construction and maintenance of bridge structures, physical and mechanical characteristics of the materials used and the effects of aggressive media.
   The development of a simulation model and the conduct of a series of simulation experiments made it possible to substantiate correlation, regression and analytical dependences reflecting the statistical characteristics of the area of corrosion damage to reinforcement and the operating time for failure of superstructure beams in a wide range of effects of loads, deicing materials, and chemically active gases.
   The proposed methodological approach allows design and road maintenance organizations to predict the inter-repair service life of spans of reinforced concrete bridges, to develop measures to increase their durability and reliability, which helps reduce costs not only for the operation of bridge structures, but also the timely elimination of the consequences of premature destruction.

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