Articles published in the issue 12, 2020

Change of hardness on the rail head running surface in the welded joint zone during operation

Keywords: welded joint rail head, hardness, running band, passed tonnage, transverse and longitudinal profile.

Bogdanov Oleg — Ph.D., Leading Engineer of Track and Special Rolling Stock Department of JSC «VNIKTI». Kolomna, Russian Federation. E-mail: bogdanov-ok@vnikti.com

Akashev Mikhail — Leading Engineer of Track and Special Rolling Stock Department of JSC «VNIKTI». Kolomna, Russian Federation. E-mail: akashev-mg@vnikti.com

Abstract. The change of metal hardness on the rail head running surface in the welded joint zone of the rails during operation is discussed in the article. The distribution of hardness within the joint zone in the longitudinal and transverse directions is obtained as the passed tonnage increases. It has been established that within the welded joint zone on the rail head running surface in the longitudinal direction, three areas of reduced hardness are formed, the change in hardness has a W-shape. Saddles were found in the cross section within the joint zone, the hardness of which after passing 432,8 million tons of gross, decreases to 286 HB.

Citation: Bogdanov O.K., Akashev M.G. Change of hardness on the rail head running surface in the welded joint zone during operation // Railway Track and Track Facilities. 2020. № 12. P. 7—9.

Roller devices for improving the operation of reverse gear for switches

Keywords: switchboard, rollers, reverse gear, classification, scope of application.

Shishkina Irina — Ph.D., associate Professor of the Department of «Transport construction» of the Russian University of Transport. Moscow, Russia. E-mail: Shishkinaira@inbox.ru

Zverkova Nadezhda — engineer, teacher of the Moscow College of transport of the Russian University of Transport (MIIT). Moscow, Russia. E-mail: N.zverkova@mail.ru

Elesina Larisa — engineer, chief specialist of the Department of secondary vocational education of the Moscow College of transport of the Russian University of Transport (MIIT). Moscow, Russia. E-mail: Laelesina@mail.ru

Abstract. The article analyzes the use of roller devices to improve the operation of translation mechanisms of switches. The use of roller devices should be regulated depending on the designs and other technical characteristics of the manufactured switches, in order to avoid failures and ensure the safe and uninterrupted operation of such complex technical structures as the switch. Effective use of roller devices requires a comprehensive approach to their implementation. Otherwise, the effect of the application is insignificant.

Citation: Shishkina I.V., Zverkova N.V., Elesina L.A. Roller devices for improving the operation of reverse gear for switches // Railway Track and Track Facilities. 2020. № 12. PР. 12—14. (In Russian)

Assessment of structures of the upper structure of the subway path according to reliability criteria

Keywords: railway track, subway, track facilities, reliability, track structure, rail gauge geometry.

Zamukhovsky Alexander — Ph.D., Department «Rail track and track facilities», RTU (MIIT). Moscow, Russia. E-mail: miit.pph@inbox.ru. SPIN-code: 4211-6690.

Pogosyan David — Postgraduate student, Department «Rail track and track facilities», RTU (MIIT). Moscow, Russia. E-mail: david32243@rambler.ru. SPIN-code: 6639-3335.

Abstract. Intensive expansion of the Moscow Metro polygon due to new construction, the need to reconstruct the first lines, reducing the time for its maintenance and insufficient material and labor resources require the selection of the optimal design of the upper structure. The article sets out an approach to solving this problem based on the calculation of indicators of reliability and safety of its operation.

Estimation of minimal damaging stresses under cyclic loading of steel riveted bridge spans

Keywords: bridges, metal, spans structures, cyclic loading, submicro cracks, fatigue failures, endurance limit.

Kondratov Valery — Ph.D., Head of Department of tests of bridges and structures Joint-stock company «Bridge research Institute». St.Peterburg, Russia. E-mail: imostov@yandex.ru

Rupasova Inna — Ph.D., leading researcher Joint-stock company «Bridge research Institute». St.Peterburg, Russia. E-mail: ruinna@yandex.ru

Abstract. The article presents the results of research on the estimation of the value of minimal damaging stresses under cyclic loading of steel riveted spans of railway bridges. The gradual accumulation of irreversible distortions of the steel crystal lattice in the area of rivet holes during the span structure’s service life has been experimentally established. Cyclic loading of low-carbon steel at stresses below the endurance limit leads to distortion of the crystal lattice and the formation of submicrotracks in the metal structure, which ultimately affects the accelerated formation of microcracks at the stress level exceeding the endurance limit. Innovative freight cars with linear loads of the order of 8–10 tf/m will cause relatively higher stresses in nodal joints with single-cut rivets than circulating trains, and, as a result, contribute to the accelerated formation of fatigue damage in the areas of riveted openings.

An integrated approach to ensuring the durability of welded spans of railway bridges

Keywords: welded metal spans, fatigue cracks, an integrated approach to ensuring fatigue life, vibration processing, infrared thermography, high-frequency mechanical forging (HFMP), structural and design methods, induction brazing, MIG-brazing.

Usoltsev Andrey — Head of the Department, Siberian Research Institute of Bridges, Siberian State University of Railway Engineering. Novosibirsk, Russia. E-mail: uam@stu.ru. SPIN-code: 6167-6140.

Popova Ekaterina — Senior Researcher, Siberian Research Institute of Bridges, Siberian State University of Railway Engineering. Novosibirsk, Russia. E-mail: kgp@stu.ru

Malikov Mikhail — engineer of the Siberian Research Institute of Bridges, Siberian State University of Railway Engineering. Novosibirsk, Russia. E-mail: mixakad@mail.ru

Abstract. In recent years, there has been a massive increase in the formation of fatigue cracks in welded spans. In this situation, only an integrated approach based on the use of innovative technologies at all stages of the life cycle, will be able to solve the problem of increasing the fatigue life of welded metal spans of railway bridges. Proper design of welded structures will allow avoiding structural stress concentrators.

On the issue of organizing fleets of track cars

Keywords: Railways, track machines, technical operation and repair, system approach.

Grinchar Nikolay — D.Sci, professor of the Department «Land transport and technological means» of the Russian University of Transport (MIIT). Moscow, Russia. E-mail: nggrin@yandex.ru

Abstract. The article discusses the prerequisites for the organization of a rational scheme of maintenance and repairs of track vehicles. It is shown that such a scheme can be implemented using a scientifically based system approach. The main stages of development of the operation scheme that form a hierarchical set are defined and presented.

Monitoring the condition of the roadbed

Keywords: roadbed, monitoring, classification, diagnostic car, unstable districts, yielding, ranking, spectrum analysis, georadiolocation, cutoff, database, StabWay.

Sedelkin Yuri — deputy general Director of INFOTRANS. Samara, Russia. E-mail: sedelkin@infotrans-logistic.ru

Atapin Vitaliy — Ph.D., Senior Lecturer of the department «Rail and railway equipment» of Samara State Transport University, lead engineer of methodical and technological department of INFOTRANS. Samara, Russia. E-mail: vitap88@rambler.ru, atapin@infotrans-logistic.ru

Chekin Artem — lector of the department «Rail and railway equipment» of Samara State Transport University, lead engineer of methodical and technological department of INFOTRANS. Samara, Russia. E-mail: chekin@infotrans-logistic.ru

Abstract. The article emphasizes the importance of the roadbed as one of the main elements of the railway track construction. It describes the main stages of implementation and development of the software «monitoring of the roadbed» (software «StabWay»), which is currently one of the modern methods for assessing the stability of the path at the objects of the roadbed. A block diagram of the software «StabWay» and the technology for determining unstable sections of the roadbed are presented. Examples of reporting output forms are provided. The classification of various types of instability is given. The technology of determining unstable districts using the «EXPERT» system is described, as well as the prospects for its development are presented.

Stability of slopes of drains in soils with layered texture

Keywords: soil, texture, excavation, water filtration, slope stability, gabion.

Smolyanitsky Leonid — Ph.D, associate Proessor Voronezh branch of Rostov State Transport University. Voronezh, Russia. E-mail: L.smol37@list.ru

Abstract. The article considers the widespread case when layered texture soils occur in the slopes of road recesses (for example, intercalation of clay and sandy soils), and temporary aquifers are created in sandy soils during periods of intense snowmelt and prolonged rainfall. Slopes lose stability. A method for calculating the stability and depth of fracture of the slopes of the notches.