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This article contains results of experimental studies on the formation of corrosion products as a result of aggressive environment and electric currents action on the reinforced concrete structures. There are discussed a method of creating models with artificial electrocorrosion under conditions close to real working. The results of testing models using the X-ray method and modeling their strength characteristics are presented.

The article shows that the replacement of concrete poles should be based on their actual corrosion state. Authors propose a new method for determining the corrosion state of the contact system concrete poles underground part, which allows to carry out measurements on the two poles at the same time. In this case, second pole acts as a current electrode. There is a formulas for determining the resistance of concrete, resistance and capacity of «steel - concrete» interface region. This algebraical expressions are results of the transient process analysis for the contact system poles equivalent circuit. The values of these parameters define the corrosion state pole in the underground part. Using of the proposed method will significantly reduce the time and labor costs of diagnostic procedures.

The article discusses the possibility of extending the service life of passenger cars. The analysis of the state of the passenger car fleet has established that the rate of replenishment of reserved cars has been reduced by more than 40 % over the past 10 years, therefore, it is possible to ensure coverage and replenishment of the retirement of rolling stock of this type after the expiration of the standard service life only by extending the service life of existing cars by carrying out capital repairs with the establishment of a new standard service life. When analyzing the power frame of a reserved seat passenger car, it was found that the greatest static and dynamic loads are perceived by its center beam. It is precisely because of the stresses arising in it that an assessment is formed of the further possibility of operating a car both during its life cycle and further use in diagnostics for the possibility of assigning a new service life to it during overhaul repairs. Studies of a number of elements of center beams cut from passenger cars that have expired the standard period have established that the main characteristics of the metal meet the requirements of safety standards, this indicates that the safety margin and resource inherent in them has not been fully depleted. In the study of the presence of residual stresses that have arisen in the elements cut from the ridge beams, depending on the depth of etching carried out according to the method of N. N. Davidenkov in accordance with the TSNIITmash methodology, the most vulnerable and dangerous places of corrosion that require more careful control during the car maintenance and scheduled preventive repairs were identified. In order to reduce the development of residual stresses and the corrosive effect on the load-bearing frame of a second-class car, recommendations and technological operations have been developed for strengthening the ridge beam by the method of shot-blasting with the formation of a uniform fine-pored structure, which ensures uniform application of paint and varnish coating.

Corrosion processes at various constructive changes of grounding system of traction substation are considered: construction of new cable lines, expansion of the territory of substation, etc. Calculation of corrosion processes of the grounding system consisting of three electrodes is carried out: steel in concrete, the metal gauze in soil, a steel vertical electrode in soil. Results of calculations are presented, the analysis of corrosion processes is made under various conditions.

The mathematical method of calculation of currents of corrosion of two models of grounding models - ekvipotentsialny and nonkvipotentsialny is presented. Soil and electric corrosion of both models is considered. The mathematical method of calculation of sizes of corrosion currents and potentials will allow to estimate a corrosion condition of elements of grounding system of traction substation.

Now there is no efficient decision to estimate a corrosion condition of an underground part of reinforced concrete support of contact network which is not demanding digging of a support. This problem makes actual a task of development of a hardware and software system of definition of a corrosion condition of an underground part of reinforced concrete support of contact network. As a result of work the software module allowing to realize panoramic shooting of an internal surface of an underground part of a support, to increase quality of the received images, to carry out searching of inhomogeneities and to determine their geometrical parameters, and also to make the analysis of the found inhomogeneities. Implementation of results of work will allow to reduce time and labor costs, and also to increase efficiency of diagnostic works on support of contact network.

Data on corrosion fatigue damages of a sole of rails (defect 69) on the railroads of Russia are submitted. It is established that 69 the corrosion fatigue resulting from moistening of a sole in a zone of contact with subrail laying in combination with the high level of the stretching tension in a rail sole is the reason of breaks of rails on defect. The analysis of statistical data on refusals of rails on defect 69 in the West Siberian management of infrastructure showed that failure rate grows to an operating time of the tonnage of 800 million t gross and has fatigue character. On sites of a way with a complicated plan and a profile failure rate is 3 - 4 times higher, than on quiet Trans-Siberian to the course. Results of the analysis of data are shown and measures for increase of reliability of the rail lashes having tendency to formation of defects on a code 69 are offered.