Rail Track Research Articles

Factors reducing the detectability of train horns by road users: A laboratory study

Level crossing safety is a well-researched safety issue worldwide, but little attention has been placed on the safety benefits of using train horns when a train approaches a level crossing. Given train horns' adverse effects on the health and well-being of residents living near rail tracks, the use of train horns must be beneficial to safety. The current study sought to determine in a laboratory environment whether road users (N = 31) can detect the range of train horns observed in Australia in terms of loudness and duration, using high-definition audio recordings from railway crossings. A repeated measures design was used to evaluate the effects of key factors likely to influence the detectability of train horns, including, visual and auditory distractive tasks, hearing loss and environmental noise (crossing bells). Train horn detectability was assessed based on participants' accuracy and reaction times. Results indicated the duration of the train horn had the most influential effect on the detectability of train horns, with short-duration train horns less likely to be detected. The presence of bells at a crossing was the second most important factor that limited train horn detection. Train horn loudness also affected detectability: faint blasts were less likely to be noticed, while loudest blasts were more likely to be noticed. However, loud horns reduced the ability to detect the side from which the train was approaching and may result in longer times to detect the train, in the field. The auditory distractive task reduced the train horn detection accuracy and increased reaction time. However, the visual distractive task and medium to severe hearing loss were not found to affect train horn detection. This laboratory study is the first to provide a broad understanding of the factors that affect the detectability of Australian train horns by road users. The findings from this study provide important insights into ways to reduce the use and modify the practice to mitigate the negative effects of train horns while maintaining the safety of road users.

Trajectory evaluation using repeated rail-bound measurements

Abstract Many applications today require the precise determination of the position and orientation of a moving platform over time. However, especially in safety-critical areas, it is also important to derive quality characteristics of the trajectory estimation. This allows verification that sensors are operating within the precision and accuracy required for the application. In this paper, we propose a methodology for trajectory evaluation and address the challenges involved. Our approach is based on repeated measurements obtained using a closed loop rail track and allows the evaluation of the trajectory estimation in terms of precision and accuracy. Starting with the chronologically ordered raw data, the methodology first spatially sorts the measurements and then approximates them to a mean trajectory. The deviations between the single pose observations and the mean trajectory indicate the precision of the observed poses. With the addition of a higher-order reference, our methodology also determines the accuracy of the system under test. The applicability of our method is demonstrated by an exemplary evaluation of a low-cost inertial navigation system.

Linking Police and EMS Records: An Approach to Strengthen Bicyclist Injury Reporting

Bicyclist injuries are underreported in police crash databases. We explored the value of linking police-reported crash data with emergency medical services (EMS) data within the City of Milwaukee, WI. Using data from 2014 to 2016, we linked records by inspection (identical date, similar time of day, and similar roadway location) and found 154 matching records between the two databases (representing 41% of the 375 police crash records and 44% of the 348 EMS injury records). Matched records were more likely to involve fatal and severe injuries according to police-assessed injury ratings. The two datasets also provided different insights into bicyclist injury crashes. Injuries captured only by police reports were significantly more likely than injuries captured only by EMS to be along high-traffic streets and commercial districts and significantly less likely to be near parks. Nearly all police records described the driver and bicyclist movements (e.g., turning) and operating behaviors (e.g., failure to yield) that had contributed to the crash. In addition to capturing more bicyclist injury events, EMS records revealed additional information about their causes. Twenty-three percent of EMS narratives described falls. These falls involved intoxication, striking a curb, swerving to avoid automobiles or other bicyclists, doing tricks, and getting a tire caught in rail tracks. Another 11% described bicyclists striking objects, including a bus stop shelter, stop sign, fire hydrant, and fence. Although there are strengths and limitations to both datasets, linking police-reported crashes with EMS records produced a broader understanding of bicyclist injuries.

Response Analysis of a Ballasted Rail Track Constructed on Soft Soil by 3D Modeling

The displacement, stress, and strain distributions of railway embankments on the soft deltaic deposit of the Ganges–Brahmaputra floodplain are investigated. A numerical model developed in general-purpose finite element software is used to simulate the design train load on a deltaic deposit for a 100 km/hr rail speed. The numerical analysis analogy is grounded in the spring model, where a beam under the unit load is modeled based on the Winkler foundation model concept. In the moving load simulation on soil, the static point load relating to the axle load is assigned in the form of a dynamic multiplier, determined using auxiliary software. The calculated shear force in terms of the influence line is applied as a dynamic multiplier. The numerical results demonstrate that under a dynamic train load, the loose ballast undergoes larger and more erratic displacement than the subballast. Comparative analysis between varying subballast stiffnesses shows that stiffer subballast yields smaller displacements. Moreover, a high subballast stiffness can counterbalance the potential of forming permanent deformation by generating lower strains. However, a stiffer subballast does not play a prominent role in reducing the displacement of ballast or vertical stresses. The subgrade is found to carry the maximum load, withstanding the maximum vertical stress; thus, the importance of using an improved subgrade with higher stiffness is also observed. A greater subgrade stiffness improves its load-carrying capacity but fails to reduce the tension responsible for the lateral spreading of the soft subsoil. To reduce the high radial strain, the effects of improving the stiffness properties of two immediately adjacent soft soil layers are numerically investigated. The improvement of subsoil alone is effective in reducing the radial strain, whereas the improvement of both subgrade and subsoil produces further reductions. The critical train speed generating the maximum displacement is identified as 120 km/hr, and the dynamic velocity amplitude decreases with depth. Finally, an allowable limit of rail embankment settlement on a soft deltaic deposit is observed.

Application of Sensors for Incorrect Behavior Identification in a Transport System.

This article focuses on cranes that are moving on a fixed crane track. There are specific problems and malfunctions arising during the operation of these cranes caused mainly by the crane skewing phenomenon. Crane skewing induces undesirable additional forces as a result of force contact between the crane wheel flange and the head of the crane track rail. This negative phenomenon induces additional stress in the crane construction as well as wear of the crane components and, finally, a global reduction of the crane operational durability and reliability. There is described in this article a methodology and data processing for the experimental measurement targeted on the crane skewing, namely in the case of a bridge crane installed in a laboratory. The crane skewing phenomenon was experimentally induced by an intentional disruption of speed synchronization of the crane travel drives. The intensity of the crane skewing was measured by means of the strain gauge sensors. A suitable application of the measuring sensors, together with the utilization of the drive control algorithm, enables efficiency to eliminate crane skewing and also prevent its occurrence.

Sources of Continuous Welded Rail Tracks Troubles

Sources of Continuous Welded Rail Tracks Troubles

Performance analysis of subgrade in asphaltic rail track design and Indonesia’s existing ballasted track

AbstractDue to subgrade-related concerns, the performance of Indonesia’s ballasted track continues to be significant impediments for the Indonesian railway stakeholders’ intention to increase the speed of passenger train operations. This study aims to examine the vertical compressive stress in the subgrade of Indonesia’s ballasted track and two asphaltic rail track designs, asphaltic overlayment and asphaltic underlayment, under various cyclic loading conditions based on three different train speeds, 120 (low speed), 240 (medium speed), and 360 kph (high speed). The AC layer thicknesses for each asphaltic rail track design are as follows: 0.1, 0.2, 0.3, and 0.4 m for asphaltic underlayment, and 0.075, 0.15, 0.225, and 0.3 m for asphaltic overlayment. 2D finite element models and simulations were used to capture and predict the subgrade’s vertical compressive stress performance. The most obvious finding to emerge from this study is that the asphaltic overlayment track has a greater capacity for transmitting and decreasing stresses from the top structure to subgrade layer than the asphaltic underlayment track and the Indonesia’ ballasted track, respectively. This research can shed light on the prospective application of asphaltic rail track to the Indonesian rail network for the faster passenger trains operation.

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

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.

Generation and directional decomposition of guided waves for finite-range defect detection in rail tracks

Abstract Railway tracks exhibit a complex, sudden alteration in their cross-sectional configuration. Generating guided waves within thick rail tracks using conventional guided wave transducers is challenging. This research employs directional decomposition to comprehend how guided waves form within the rail. These waves arise from constructive interference between multiple reflected bulk waves, which are induced by point forces on the top surface of the railhead or diffracted from cracks in the rail structure. This study simulates finite-range detection of rail defects using finite element analysis to demonstrate a potential application to the guided wave rail inspection car. The transmitter and a series of monitoring points are located on the same side of the rail defect in the pitch-catch configuration. The transmitting guided waves often hide the small backscatter waves induced by defects. A directional filter extracts the small backscatter signals from the entire received data. A 100 kHz tone burst actuates on the top surface of the rail in three orthogonal directions. Numerical findings demonstrate that vertical and tangential excitations are suitable for detecting defects in the railhead and lower region, while transverse excitation and detection are appropriate for identifying defects in the rail web. The application of directional decomposition provides valuable insights into the complex process of backscatter waves arising from rail track defects.

FORECASTING THE WORK RESOURCE OF THE RAILS IN DIFFERENT CONDITIONS OF OPERATION OF THE RAILWAY TRACK

In different operating conditions of the railway track, the service life of the rails is different. This indicates that there are external factors that have a significant impact on the process of rail wear. In the work, the analysis of influential factors was carried out and their degree of influence was determined in comparison with each other and in the statistical population.
 To study this problem, the most difficult section of the Slavsko-Lavochne-Beskid-Volovets track on the regional branch of Lviv Railway was chosen. The collection and processing of statistical data was carried out, measurements of the rail track and measurements of rail wear were carried out.
 The process of lateral wear of the rail depends on various factors, among which it is possible to single out those that are the same for the entire curve, and those that are different for different intersections of the curve. For the entire curve, the tonnage passed, the radius, the set speed, the rise of the outer rail, the longitudinal slope, the type of rails and the binding are the same. These parameters can be called global for the curve, and the wear that depends on them is global. Along the curve, there are local irregularities, that is, deviations in the plan, profile, pattern and inclination of the rail in the middle of the track. These parameters can be called local for the curve, and the wear that depends on them is local. Local wear is additional. The total side wear can be manifested to a greater or lesser extent depending on external conditions: lubrication, sanding of rails, excessive impact of wheels, which is taken into account by the coefficient of external conditions.
 The results of track measurements show that when a horizontal unevenness appears on a curved section, the bending radius increases, and in such places, there is an increase in lateral wear. When the width of the track in the curves exceeds the established norms, there is also an increase in the amount of wear. Over-inflating causes the wheelset to slide to the inner rail. At the same time, the larger rolling circle is not on the outer wheel, but on the inner one. The vertical force transmitted from the wheel to the rail is also greater along the inner thread. This leads to slipping of the wheel on the outer thread, which increases the lateral wear of the rail. As the measurements showed, when the slope of the rail increases from 1:20 to 1:10, the amount of lateral wear increases. The use of lubricators that lubricate the side surface of the rail head can increase its service life by 3 times. An increase in the surface roughness of the rail by 20 μm leads to a decrease in wear resistance by 20-25%. Based on the received empirical data, a mathematical model of lateral wear of the rail head based on 16 parameters was created.
 Based on the norms of permissible wear of the rails and the created mathematical model, the service life of the rails is determined in the work depending on the curvature of the track. Forecasting the resource of rails allows to implement resource-saving in railway transport.

Experimental determination of dynamic characteristics of a railway track

It is known a priori that vibrations that occur in the elements of the track structure during the passage of a train load are a superposition of free and forced mechanical vibrations. It has been established that the range of oscillation frequencies of the elements of the track superstructure includes oscillations with a frequency from tens to hundreds and thousands of hertz. However, the influence of vibrations on the track and their dependence, in turn, on the design of the track, has not been fully studied, which causes controversy between specialists in this matter. There is an opinion that in intermediate fastenings, the main role is played by an elastic gasket, which ensures the vertical rigidity of the rail-sleeper assembly. It has been experimentally established that in the frequency range below the frequency of free oscillations of rail fastenings, the force applied to the upper surface of the elastic gasket is transferred to the lower surface in an unchanged form.
 The article discusses the vibrations that occur in the elements of the upper structure of the track (rails, sleepers, rail fastenings, ballast base) during the passage of a moving load, which significantly affect the strength, and, consequently, the durability of both the elements themselves and the railway track generally. Vibrograms, oscillograms, accelerograms of rail oscillations and their spectra during the passage of TALGO are presented. At present, the VOSSLOH fastening, developed in Germany, has been widely used in the construction of tracks on high-speed railways of the Republic of Kazakhstan. In this regard, there is a need for a comprehensive study of the operation of this type of fastening under a train load

Automatic Obstacle Detection Method for the Train Based on Deep Learning

Automatic obstacle detection is of great significance for improving the safety of train operation. However, the existing autonomous operation of trains mainly depends on the signaling control system and lacks the extra equipment to perceive the environment. To further enhance the efficiency and safety of the widely deployed fully automatic operation (FAO) systems of the train, this study proposes an intelligent obstacle detection system based on deep learning. It collects perceptual information from industrial cameras and light detection and ranging (LiDAR), and mainly implements the functionality including rail region detection, obstacle detection, and visual–LiDAR fusion. Specifically, the first two parts adopt deep convolutional neural network (CNN) algorithms for semantic segmentation and object detection to pixel-wisely identify the rail track area ahead and detect the potential obstacles on the rail track, respectively. The visual–LiDAR fusion part integrates the visual data with the LiDAR data to achieve environmental perception for all weather conditions. It can also determine the geometric relationship between the rail track and obstacles to decide whether to trigger a warning alarm. Experimental results show that the system proposed in this study has strong performance and robustness. The system perception rate (precision) is 99.994% and the recall rate reaches 100%. The system, applied to the metro Hong Kong Tsuen Wan line, effectively improves the safety of urban rail train operation.

Tram-track cycling injuries: a significant public health issue

AimMany cycling collisions occur due to human error, cycling ability, distraction or infrastructure. One such infrastructural issue for cyclists sharing the road with tram lines is where the wheel of the bicycle gets caught in the rail track itself or in a gap between the rail and the road margin resulting in a sudden stall of the bicycle and potentially significant injury. This study aims to describe the crash characteristics of tram-track cycling collisions and their associated injuries.MethodsA retrospective chart review was conducted over 2 years, looking at cyclists that presented to St James’s Emergency Department (ED) following injuries sustained due to a bicycle wheel catching in the on-road tram tracks.ResultsForty-eight patients were identified over a 2-year period. Sixty per cent of cyclists sustained limb fractures with 14% requiring orthopaedic surgery. Fifty per cent of patients were not wearing a helmet at the time of the incident and 54% of the collisions occurred around Dublin city centre during rush hour.ConclusionFurther prospective multi-centre studies are required to properly describe the magnitude cycling accidents around the Luas tracks and inform future public health measures in this area.

Mempercepat Waktu Pelaksanaan Proyek Pembangunan Jalur Ganda Kereta Api Antara Mojokerto-Sepanjang Melalui Penjadwalan Line of Balance

In construction management, project scheduling is an important thing to note. The project schedule is a means of determining proper duration, controlling implementation progress, and allocating resources efficiently. Improper scheduling will have an impact on project delays. the project for the construction of a double track railway across the south of Java between Mojokerto-Sepanjang is planned to be completed in 60 weeks with overlapping activities due to changes in activities. This double track rail project is an ongoing project. This research aims to find out the project implementation time using the Line of Balance. The development project has a length of 3011.23 m. the Line of Balance method is carried out by determining the dependency logic, preparing a Line Of Balance schedule, drawing a Line Of Balance graph, and determining the production speed. The results of the study show that the line of balance schedule in the existing conditions has lines of intersection between jobs. The intersection indicates that there is overlapping work. For this reason, improvements are made by changing the dependency logic from work that was originally parallel to not parallel. The results of improvements made by reducing the duration per work cycle by 1 week revealed that the duration of the project could be accelerated to 38 weeks. So that the scheduling can be used to speed up the time of implementation of project activities.

МЕТОДИКА ОПРЕДЕЛЕНИЯ ХАРАКТЕРИСТИК ВИБРОПРОЧНОСТИ КОНСТРУКЦИИ ПРИ ВЫСОКОСКОРОСТНЫХ ТРЕКОВЫХ ИСПЫТАНИЯХ АВИАЦИОННОЙ ТЕХНИКИ

Achieving the speed limits by ballistic aircraft is a priority, relevant and new technical challenge for the present. Track tests of such products are one of the final stages, confirming their practical performance and efficiency. Testing of products of aviation and rocket technology at the "Rocket Rail Track 3500" FKP "GkNIPAS" named after L.K. Safronov allow to accurately simulate the real conditions in which they are operated. The experimental setup includes a two-rail track, made on a special base, which excludes the unacceptable deflection of the R65 rail, with its fixing every 0.5 m by a special embedment design. The rail track has an acceleration section with an angle of attack of 2º and a length of 2500 m and a deceleration section. The test object is placed on the missile track carriage in such a way as to exclude the impact on it of shock waves reflected from the elements of the carriage and relief. Solid propellant rocket engines are installed on the carriage, which provide the necessary thrust. The sliding bearings of the rocket carriage cover the head of the rails. The thrust of the starting rocket engines provides the necessary acceleration to achieve the maximum values of the required test speed. Track high-speed tests of special equipment objects are accompanied by intense vibration and shock loading of the structure. As the speed of products increases above 600 m/s, as tests have shown, the amplitude of elastic oscillations of the structure can reach the maximum values permissible from the strength conditions. Experimental and theoretical study of vibration and shock effects on the structure of a track carriage with test objects under the conditions of an existing rail track is an urgent task for practice.

Stochastic Mechanism of Shock Disturbances of Rocket Sleigh Supports during High-Speed Track Testing of Aviation Equipment

Tests of ballistic aircraft on rail tracks in conditions close to real ones are an economically viable alternative to flight tests. Rocket rail tracks exist in the USA, Canada, France, China and a number of other countries. The article con-siders potentially self-oscillating mechanical systems that have a threshold mechanism for the transition from a noise vibrational stable state to a self-oscillatory one, depending on the mode parameters. An algorithm for estimating the damping coefficient of the harmonic components of a particular mode of a complex process is proposed. As an indicator of energy loss of the oscillatory component during resonant interaction, the value of the density of the power spectrum related to the width of the frequency range is taken. Based on the solution of the Fokker-Planck equation for a stochastic process, estimates of the “drift” and “diffusion” coefficients are obtained. A technique for estimating the state of potentially self-oscillatory systems in the form of a set of probabilistic stochastic characteristics is proposed. According to the experimental data of vibration accelerations for the structural elements of the rocket sled with the test object, according to the proposed method, it is possible to make the contribution of the self-oscillations of the elements, if they are pre-sent in a complex vibration process, and also to make estimates of their vibration strength at resonances.

SUSTAINABLE TRANSPORTATION SYSTEM

Global transport policy and planning now prioritise sustainability above all else. Similar to sustainable development, the definition of sustainable transportation is wide, allowing for the designation of some kilometer and policies as “sustainable” even when they follow standard operating procedures. Therefore, it is imperative that sustainability concepts be properly integrated into and applied to the transportation sector. Frameworks for performance measurement provide an efficient means of doing this. Much work has gone into comprehending and implementing the idea of sustainable development in the transport sector during the last 20 years.1. We may get knowledge from a plethora of study and experience in this area. However, there hasn’t been much headway in implementing more environmentally friendly modes of transportation. Given the rising demand for infrastructure and mobility in many areas, the detrimental effects of transport are probably only going to get worse (Dulca 2013; AfDB et al. 2012). For instance, the expansion in passenger and freight traffic, particularly in emerging nations, is predicted to need over 25 million paved road lane kilometers and 335,000 rail track kilometers worldwide by 2050 (Dulca 2013). To put this into context, the total length of all road and railway networks worldwide would have increased by 60% as a result (ibid.). In line with these projections, oil consumption is anticipated to rise in 2035, mostly due to demand from China and India, while it is likely to decline in the Organisation for Economic Co-operation and Development.

THE DIRECTIONS OF ELECTRIC VEHICLE MODULES FOR ANIMALS’ SERVICING ON "SMART" FARMS AND COMPLEXES DEVELOPMENT

A conceptual approach for animals’ servicing logistical problems solving on dairy and pig complexes is considered. It is proposed two types of electric vehicle modules for electric tractor and chassis’s performance developing. The first is for trailed adapters (feed mixer, stall cleaner, litter spreader and others) working. The second one is for adapters installed on a universal platform (chassis) working. Adapters can be as follows: a feed mixer, a milking machine for cows’ milking in boxes, disinfecting equipment, calves’ drinking installations and feeds and hay mixed distributing, a scraper for stall and manure cleaning and others. Examples of this direction’s practical developments in the RUP "NPC of the NPC NAS of Belarus on agricultural mechanization" are given. The UVP-3 mobile drinking machine on a rail track has been developed, as well as an installation for calves’ feed preparing and distributing, including liquid nutrient mixtures, hay and dry compound feed. Developed under the guidance of professor V.I. Peredni, trailed feed dispensers-mixers that feed in intersecting streams with minimal energy consumption mixing, can with a small drive’s upgrade be towed in cowsheds by an electric car without exhaust gases and noise, i. e. without stress, that cow yield and milk quality increasing. Two types of electric mobile feed dispensers for feed distribution on pig farms - on the electric car’s basis controlled by an operator standing on the electric car’s platform with control levers, and on electric car’s basis with steering have been developed.

Ensuring the safety of rolling stock movement when entering transition curves

The main factor in the issue of the safety of the rolling stock movement in the rail track is the change in the magnitude of the lateral forces arising from the interaction of the wheel with the rail. The dynamics of changes in lateral forces directly depends on the increase in rolling stock speeds in curves and, especially, in transition curves. To prevent the sudden appearance of centrifugal force, the outer rail is elevated, the track is broadened when moving from a straight line to a circular curve and a transition curve of variable curvature r = l / p, where p is the variable radius of the curve. Within the transition curve, the current elevation h of the outer rail over the inner rail must be proportional to the current curvature value, including at the end of the transition curve, all these factors leading to a sharp dynamic increase in lateral forces. In this case, the elevation h0 of the rail and the curvature r0 = 1/R are the parameters of the circular curve. Due to the fact that r, h and track width S are variables within the transition curve, in case the widening in a circular curve is intended when moving along the transition curve, additional forces and moments arise not present either on a straight line or on a circular curve. It is necessary for any additional force factors (forces and moments) to change gradually and be equal to zero at the beginning (BTC) and end (ETC) of the transition curve, and for the absolute values and intensities (gradients) of their changes within the transition curve not to exceed the allowable values, which is provided by complying with the requirements specified in table.1.

Разработка программно-аппаратного комплекса управления вагонеткой на основе нейронных сетей

In the architectural world, management is inseparable from technical progress. In order for the management process to take place with greater efficiency, it is necessary to constantly introduce various technologies. One of the technologies in demand is artificial intelligence. This technology is able to imitate human behavior to perform tasks: prediction, control system design, fault detection, classification, etc. The solution of the blocking problem in this paper is applied to the transport of carbohydrates. The feasibility of using detection technology in special operating conditions. The development of neural networks and their application in various areas associated with high human activity in workplaces characterized by a high level of danger, optimization of routine processes are pre-requisites for the development of this software and hardware complex. The condition for considering the process of controlling the movement of the trolley, because this is the most identified and simplest detection of coal content in deposits. The aim of the work is to develop a hardware-software complex for controlling a trolley based on neural networks, which is a system for detecting events (empty or detected) of a trolley and controlling the direction of movement along the rail tracks. For this purpose, the author analyzed the characteristics of the object, conducted a study of the literature on the topic, assembled a sample of the system, and developed a software product. The results of modeling and withdrawal of the work done are given. The trolley was controlled thanks to the game of the Arduino UNO microcontroller.