Potential for external reinforcement of insulated rail joints

This paper aims to investigate alternative ways of reducing the deterioration and failure of railway track insulated rail joints (IRJs). Joints deteriorate faster than rail initially due to the structural discontinuity present. This weakness results in both extra displacement as a consequence of applied load and the dynamic force that results as a consequence. Over time this situation worsens as the impacts and applied stresses both damage and soften the ballast and supporting subgrade under the joint. This study initially presents a static finite element model designed to simulate the mechanics of IRJs and a comparison between plain rail and a suspended insulated rail joint under various support stiffnesses. Product design options of reinforced IRJs are then chosen as input variables of the model. Results of the model are compared with field and laboratory data acquired via the Video Gauge, which is a new high-resolution optical measurement technique. Results show that the use of strap rails or more robust I-beam sections in the vicinity of the IRJ to stiffen the support structure can significantly reduce the displacement and the subsequent dip angle seen at an IRJ. This potentially presents a means of improving the IRJ behaviour. Their impact becomes more significant for soft support conditions. Although these results are indicative for new IRJ conditions, field measurements indicate that the magnitude of deflection of IRJs is a result of the structural discontinuity of the rail, the dynamic P2 force, the wheel condition, the degraded ballast and it significantly increases with time under repeated load. Thus, it is recommended that careful field implementation and testing will indicate the effect of an external enhancement on the timely degradation of insulated rail joints

Multiphysics Simulation of a Battery Electric Train Operation

The changeover from diesel driven multiple units to battery electric multiple units is a challenge for operators due to the limited range of these trains. Therefore, in this paper a tool is developed and described that simulates the entire operation of a battery electric train. The tool contains a model of the track, the vehicle, the timetable and the environment. The model of the track is built on elevation profiles, radius information and speed limitation. The vehicle model is derived from an electric multiple unit suitable for local and commuter train operation. To do parametric studies or model different train units it is easily possible to change vehicle properties. Modeling the timetable and the environment allows the simulation of an entire operation day. The overall simulation model was validated and is consistent. Finally examples show the simulation possibilities and features of the tool

MOGUĆA PRIMJENA ELEKTROHIBRIDNIH VLAKOVA DESIRO ML NA LOKALNIM I REGIONALNIM PRUGAMA RH

Cilj je Europska komisija do 2050. smanjiti emisiju stakleničkih plinova iz prometa za 90 posto. U provedbi toga cilja željeznica treba odigrati važnu ulogu jer treba preuzeti većinu opsega javnoga kopnenog prijevoza. S obzirom na brojne europske neelektrificirane pruge i nastojanje da se smanji eksploatacija željezničkih vozila na dizelski pogon, uspješna rješenja nameću se kroz primjenu hibridnih baterijskih vlakova, koji mogu biti pogonjeni iz kontaktne mreže ili vlastitih baterija. Siemens Mobility proizveo je i prvi u Europi certificirao hibridni baterijski vlak Desiro ML Cityjet eco u suradnji s Austrijskim saveznim željeznicama. U ovome radu razrađene su mogućnosti primjene hibridnoga baterijskog vlaka Desiro ML Cityjet na hrvatskim prugama i u trenutačnim uvjetima na željezničkoj infrastrukturi

The assessment of track deflection and rail joint performance

Track stiffness is the one of the most critical parameters of the track structure. Its evaluation is important to assess track quality, component performance, localised faults and optimise maintenance periods and activities. Keeping the track stiffness within acceptable range of values is connected with keeping the railway network in a satisfactorily performing condition, allowing thereby upgrade of its capacity (speed, load, intensity). Current railway standards are changing to define loading and stiffness requirements for improved ballasted and ballastless performance under high speed train traffic. In recent years various techniques have been used to measure track deflection which have been also used to validate numerical models to assess various problems within the railway network. Based on recent introduction of the Video Gauge for its application in the civil engineering industry this project provides the proof of effective applicability of this DIC (Digital image correlation) tool for the accurate assessment of track deflection and the calculation of track stiffness through its effective applicability in various track conditions for assessing the stiffness of various track forms including track irregularities where abrupt change in track stiffness occur such as transition zones and rail joints. Attention is given in validation of numerical modelling of the response of insulated rail joints under the passage of wheel load within the goal to improve track performance adjacent to rail joints and contribute to the sponsoring company s product offering. This project shows a means of improving the rail joint behaviour by using external structural reinforcement, and this is presented through numerical modelling validated by laboratory and field measurements. The structural response of insulated rail joints (IRJs) under the wheel vertical load passage is presented to enhance industry understanding of the effect of critical factors of IRJ response for various IRJ types that was served as a parametric FE model template for commercial studies for product optimisation

Applicability of video gauge for the assessment of track displacement

Numerous techniques have been used for the measurement of the track displacements and consequently the assessment of track stiffness. Some of the most commonly employed are linear variable displacement transducers (LVDTs), geophones and older video monitoring techniques based on Particle Image Velocimetry (PIV). In this paper, the application of the Video Gauge, a relatively new technique, is investigated. This technique can be seen as a quick and reliable way to capture data of high quality and resolution, which can be directly employed for the evaluation of track displacement and hence stiffness.The Video Gauge is used at three different track sites measuring different ballasted track components under various train speeds and types

НОВЫЕ ТРЕБОВАНИЯ К МОТОР-ВАГОННОМУ ПОДВИЖНОМУ СОСТАВУ

Strategy of development of JSC Russian Railways and the growth in commuter passenger traffic put forward new technical requirements for electric trains. In conformity with those requirements Siemens has engineered a model of commuter electric train «Lastochka» (Swallow) with the outlook for further localization of its manufacturing in Russia. Motor rolling stock received modern braking system which is highly efficient and engineered for velocity up to 160 km / h. The article describes in details operation and design features of braking devices and its control units.Стратегия развития ОАО «РЖД» и рост рынка пригородных пассажирских перевозок предъявляют новые технические требования к электропоездам. В соответствии с этим компания «Siemens» разработала модель перспективного пригородного электропоезда «Ласточка» с последующей локализацией производства на территории России. Мотор-вагонный подвижной состав получил современную тормозную систему с высокой эффективностью и рассчитанную на скорость движения 160 км/ч. Статья подробно характеризует конструкционные и эксплуатационные особенности тормозного оборудования и управляющие им устройства.