A coordinated calculation of two processes -locomotives turnover and servicing -is described. Locomotives turnover is calculated by optimization system Labyrinth and servicing by dynamic transportation problem. Service programs integrate these processes. A model of coordinated arrival of locomotives at servicing stations is proposed. The calculation consists of three interrelated steps. The first step is the calculation of the optimal locomotive turnover without considering servicing constraints. Service program SP-1 determines stations where forced stops will take place according to the necessity of servicing and forms the basic location of locomotives for further movement to servicing stations. The second step is the calculation of the optimal arrival of locomotives at servicing stations. Service program SP-2 provides location and release time of each locomotive after servicing. The third step is the calculation of a train schedule with the consideration for the location of stopped train sets and the appearance of locomotives after servicing. Servicing program SP-3 forms the united results.

The paper considers principles of creating methods for calculation of railway stations and polygons. It shows that methods in existing instructions are theoretically based, in the essence, on logical soundness. The authors propose to consider a system approach in original statement as a scientific basis. A system is considered as a generally natural form of construction of organized matter which allows steadily functioning in environment with disorganization. An important property of the system is adaptability when structural elements enter a dynamic interaction. The authors state that in calculation models an element is assigned (consciously or not) a certain functional role that often doesn’t match a real role. Accordance of these roles is assumed as a main criterion of correctness of a calculation method. But the functional role is determined not only by properties of the element but also by a character of its interaction with other elements. That is why you can’t calculate a capacity of structural elements separately. The authors show on specific examples that it is possible to calculate the capacity only in a comprehensive model of the whole system. As a result, it is necessary to consider simulation modeling as a main method for calculation of systems of railway transport.

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When large junctions of railway polygons are studied, detailed modeling is subject to some limitations. Therefore, it is necessary to develop appropriate tools. This paper presents an aggregate (macromodeling) technique for necks and yards of railway stations. Results of calculations based on aggregate models are highly consistent with results of detailed modeling, which confirms the applicability of this modeling method to railway polygons. The proposed principles were implemented on the basis of the IMETRA simulation system. The resulting polygon model makes it possible to determine the total throughput of a polygon and to identify bottlenecks that slow down car traffic.

The paper presents the executed research on the influence of introducing scheduled trains on polygon operation carried out with the use of simulation model. The model shows the delays caused by infrastructure elements and by resources — train locomotives and car service station crews. Results show that priority trains deteriorate the parameters of polygon operation, decrease the schedule speed. Experiments with the exceed resources allowed to determine that infrastructure parameters play the main role. As a result, the introduction of priority trains is only advisable at the existence of polygon capacity reserve.