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1

Study of transitional phenomena in rail vehicle dynamics in relation to the reliability and operational state of the continuous welded rail track in terms of rail joints

Groll Witold, Sowiński Bogdan, Konowrocki Robert

Eksploatacja i Niezawodność

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2023

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Vol. 25, no. 1

art. no. 7

EN

This paper presents the results of experimental and numerical studies on reliability and monitoring issues of railway infrastructure in terms of safety and operation. The state of knowledge concerning methods of assessing track condition, in particular rail joints used in continuous welded rail track of railway lines is described. Experimental results of rail joints used in track transition zones and the results of numerical studies/tests of the rail vehicle-track model are outlined. It is demonstrated, basing on the analyses of the experimental results, that not only should the rail joints used in continuous welded rail track be diagnosed during their acceptance, but also during their operation. It is proven that the currently used methodology for testing welded rail joints applied during acceptance testing of contact track is not fully correct and leads to misinterpretation of the measurement results. Moreover, the results of numerical simulation tests presented in this paper confirm the possibility of diagnosing the condition of rail joints by any vehicle passing over such a track equipped with a suitable system.

2

Dynamics of welded rails gap and hardness of rail base

Zaitseva T. I., Blinova I. V., Uzdin A. M.

International Journal of Applied Mechanics and Engineering

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2020

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Vol. 25, no. 1

236--242

EN

The problem of gap estimation for a break of a continuous welded rail is studied. The track is represented as a semi-infinite rod on elastic-based damping. Static and dynamic solutions are obtained. It is shown that during the rail break, the dynamic factor does not exceed 1.5. We derive equations for thermal deformation of the welded rail of jointless track on an elastic foundation in the presence of the insert into the base with another characteristic stiffness. It is shown that the presence of the insertion of up to 20% of the length of the rail, with both large and small stiffness, has a little effect on the stress-strain state (SSS) of the track. The presence of a rigid insert may increase the clearance of an accidental break of the rail, which has a negative effect on traffic safety.

3

Konstrukcja nawierzchni kolejowej w łuku o małym promieniu

Błaszkiewicz D. K., Czyczyła W., Urbanek M.

Zeszyty Naukowo-Techniczne Stowarzyszenia Inżynierów i Techników Komunikacji w Krakowie. Seria: Materiały Konferencyjne

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2014

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Nr 2(104)

69--78

PL

W artykule autorzy dokonali porównania różnych typów konstrukcji nawierzchni kolejowej w łuku o małym promieniu, w celu doboru najlepszego rozwiązania zarówno pod względem finansowym jak i utrzymaniowym. W pracy przedstawiono także koncepcję dwóch innowacyjnych rozwiązań konstrukcji nawierzchni kolejowej z zastosowaniem podkładów stalowych typu V, oraz podkładów strunobetonowych typu V, które stanowią udoskonalenie dotychczas stosowanych rozwiązań.

EN

In this paper, different types of railway track for sharp curves have been compared in order to choose the best solution. Track structures have been compared with regard to financial and economic aspects. The paper presents also the concept of two innovative design solutions of track structure, i.e. steel sleepers of type V and concrete sleepers of type V, which are an essential improvement of existing constructions.

4

Problemy diagnostyki toru bezstykowego

Towpik K.

Zeszyty Naukowo-Techniczne Stowarzyszenia Inżynierów i Techników Komunikacji w Krakowie. Seria: Materiały Konferencyjne

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2009

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Nr 91, z. 149

473-491

PL

Nierównomierny rozkład sił podłużnych w szynach toru bezstykowego może doprowadzić w niekorzystnych warunkach do jego odkształcenia, a nawet wyboczenia. Zmianę rozkładu sił powoduje również wykonywanie robót utrzymania. Tradycyjna diagnostyka wykorzystuje pomiar przemieszczeń podłużnych szyn metodą punktów stałych. Zastosowanie innych metod pomiaru umożliwi w przyszłości ciągłe monitorowanie stanu toru bezstykowego.

EN

The irregular longitudinal force distribution in continuous welded rail tracks can lead to their deformation under unfavourable conditions and even to their buckling. The change of force distribution also leads to the necessity of maintenance works. The traditional diagnostics uses the measurement of longitudinal movements of tracks by the method of fixed points. The application of other measurement methods will allow for continuous monitoring of welded rail track stage.

5

Local unevenness of lengthwise profile influence on stability conditions of continuous welded rail track

Bednarek W. A.

Foundations of Civil and Environmental Engineering

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2007

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No. 10

5-23

EN

Major causes leading to CWR track buckling arc its axis initial irregularities in vertical and horizontal planes [19,20,21]. Track irregularities arise during building and operation. Principal reasons for the formation and growing of these irregularities are stable deformations of ballast. The process that leads to the formation of irregularities depends on both construction and operation condition of railway track and ravelling influence of sleeper subgrade structure around measuring position f.e. for roadbed testing by VSS plate. Initial unevenness causes additional railway grid (profile) [2,3,12,19] and railway frame (plane) bending [6,10,21,23] from a longitudinal compressive force arising due to temperature change, rolling stock braking and horizontal deformation of subsoil (mining ground). In the case of compressive longitudinal forces, a local deformed track is simultaneously bended and compressed, both being unfavourable to its stability conditions [12.13,19]. The obtained results have an essential value in the problem of vertical plane analysis of a CWR track in service [2,19,22].