Transportation Systems and Technology

At present, on the territory of the Russian Federation, there is no massive use of electrically conductive reinforced concrete structures in the electric power industry due to insufficient operating experience and a low rate of research on electrically conductive concretes.

The article compares the main characteristics of existing electrically conductive concrete. The paper shows the disadvantages of traditional concrete and existing electrically conductive concrete. The electrically conductive concrete was selected, the most suitable for further research, testing and direct modernization of the composition based on the results obtained.

The main disadvantages of existing electrically conductive concretes are the high cost and specificity of electrically conductive components and other additives, as a consequence of the amount of capital investment in mass and large-scale production, as well as the lack of operating experience as overhead supports.

Repair and reconstruction is an integral part of the life cycle of such structures as: bridges, overpasses, aqueducts. Timely maintenance and repair of bridge structures contributes to the continuous improvement of their technical level, as well as to the operational state with increasing load and intensity over time on constantly under construction highways.

This article presents the results of a study of the need to repair structures over time. The article contains a description of the types of work, as well as the terms when these works need to be performed, graphs of the volume and cost of work are given. As materials and initial data, the data of approximate turnaround periods of elements of bridge structures were taken, as well as a table of the frequency of repairs by year was compiled.

Based on the collected data, graphs of the cost and changes in the volume of work were built over time. In addition, graphs of the cost of repairing individual elements of the structure are given in relation to the total cost of the structure.

Based on the results obtained, recommendations are formulated for planning the repair of expatriated bridge structures by bridge maintenance departments. A set of measures is also proposed to eliminate existing violations and further operation of the bridge structure. A set of works for the repair of individual units and structures is recommended. Arguments are given for the need to share responsibilities between bridge operation departments during the repair of the structure.

The article analyzes the existing methods for assessing the readiness of territories for the formation of a logistics complex, examines the factors affecting the formation of the infrastructure of an innovative port logistics complex. An author's method for assessing the readiness of territories for the formation of the infrastructure of an innovative port logistics complex.

Background: to organize multimodal transportation and choose the best route option for fuel delivery, it is necessary to develop an algorithm for choosing the best solution from the considered ones. This is indicated in the Strategy of scientific and Technological Development of the Russian Railways Holding Company for the period up to 2025 and for the future of 2030 ("White Paper", where on pages 25-26 it is said about the need to develop new transport and logistics products and services in global transport chains in the development of multimodal transport and the need to develop and organize new multimodal freight transport). Federal Railway Administrations of the United States, page 127 of the White Paper, points to the need to improve the methodology of integrated multimodal transport planning at the global, national and regional levels, increase the demand for transport and logistics services, and transition to supply chain management.

Aim: to develop a method for multi-criteria rationalization of the choice of multimodal transport routes with the possibility of considering hypothetical options.

Materials and Methods: the fundamental works of leading scientists in the field of improving the efficiency of production in accordance with the needs of the economy in transportation A.V. Annenkov, P.B. Romanova were used. In the field of justification of decisions on cargo terminals, determining the volume of tank farms with the possibility of their expansion O.B. Malikov, V.N. Sapronov. The application of multi-criteria rationalization by comparing the criteria under consideration is given in the work of A.T. Osminin, which developed a scientifically based method aimed at creating analytical and control systems. In the field of risk analysis and assessment of the work of A.G. Kotenko. The works of A.Y. Akhriev, A.B. Egorov, A.A. Kalushin, V.N. Mirushkin, E.V. Pasyunin, and A.V. Savelyev were studied in the field of improving the optimization of the oil transshipment complex, and the works of M.A. Nazarov and O.M. Sergeeva in the segment of logistics of river and sea oil transportation.

Results: it consists in improving the quality of solutions to problems in the transportation of liquid fuel by means of transport in multimodal communication based on the use of the developed method. The set of criteria considered in the method allows you to set and solve transport problems with almost no restrictions on complexity, which in each case allows you to get better results.

Conclusion: Using the method in practice allows not only to objectively find the best solution from the considered ones, but also to study hypothetical transportation schemes with the possible construction of new tracks and their elements, and compare existing and new schemes by a set of criteria, including construction costs and payback time of new tracks, and as a result find the best solution to the task.

Aim: Establishment of preconditions for the introduction of a switched reluctance motor into the system of traction drive of an electric rolling stock by improving the performance of the bearing unit.

Methods: Calculations were carried out using the finite element method.

Results: It was found that the calculated values ​​of force of a one-way magnetic attraction applied to the bearing unit are tens of times higher than the permissible values. The result is accelerated wear and failure of the bearings. An algorithm is proposed which takes into account the influence of one-way magnetic attraction forces in an uneven air gap.

Conclusion: The algorithm makes it possible to change the production cycle and improve the consumer quality of the switched reluctance traction motor.

Background: The methods of calculation and elements of the technology for creating heteropolar magnetic systems of levitation, lateral stabilization and a rotor-runner of a traction linear synchronous motor for the development of the transport technology "Russian Maglev" in order to achieve an increased levitation gap of 0.2 m, reduce the threshold speed of the exit vehicle in levitation mode up to 10 km/h.

Aim: to develop methods for calculating and designing heteropolar poles from elementary permanent magnets, coils of the same type based on composite low-temperature superconductors and high-temperature tape superconductors of the second generation and a step-by-step technology for their production.

Tasks:

1. Creation of an on-board magnetic system of levitation and lateral stabilization, allowing to provide a levitation gap of 0.2 m, a threshold value of vehicle speed of 10 km/h when transition to levitation mode, to reduce stray magnetic fields to the level of the natural field of terrestrial magnetism of 50 μT;
2. Creation of a rotor-runner of a linear synchronous motor with an ironless stator with a power of 10 MW.

Methods: outlines the main calculation methodologies: "analysis" and "synthesis". The "analysis" methodology is adopted in solving the "direct" calculation problem, when the configuration of the magnetic system is set and the magnetic field in the working area is calculated, and, if necessary, the stray magnetic fields. This methodology can be effectively applied if there is experience in creating magnetic systems. Otherwise, the "synthesis" methodology is applied, which is used in solving the "inverse" calculation problem, in which the picture of the distribution of the magnetic field in the working zone is set and the configuration of the magnetic system is found (synthesized).

Results of the study performed:

1. The parameters and characteristics of high-energy permanent magnets made of rare-earth metals, low-temperature and high-temperature superconducting winding materials have been analyzed, the choice of permanent magnets and superconducting winding material has been made;
2. Calculations of the magnetic system of permanent magnets in the "Halbach assembly" and in the traditional assembly in a toothed ferromagnetic core have been carried out;
3. Calculations of a track coil with a rectangular cross-section of the winding are performed;
4. Methods for calculating and optimizing superconducting magnetic systems from a set of similar track modules have been developed;

Conclusions: The results of the performed fundamental research will allow starting the calculation, design and construction of conveyor-main passenger and freight lines of maglev transport, as well as urban public transport.