Railway Field Research Articles

Study on application of adhesives for Carbon Fiber Composites connection in High-speed Rail

At present, the high-speed train mainly made up of carbon fiber composites adopts a new flame-retardant multi-material system. It is necessary to select adhesives for the Adhesive bonding structures of different materials in order to meet the overall technical and performance requirements of high-speed trains. Through this research, mechanical performance data of several structural adhesives and sealant adhesives are obtained when they are bonded to the high-speed trains with carbon fiber composite material as the main body. Finally, the optimum adhesives for bonding different material systems in the high-speed trains are determined under different operational aging environments, which also provides data support for the formulation of connection specifications for carbon fiber reinforced composites in the field of high-speed railway. In addition, a multi-dimensional data reduction method is proposed for the analysis of sealant performance data, which is very helpful for the future analysis of big data of adhesives.

Application of low-power energy harvesting solutions in the railway field: a review

In order to ensure safety and reliability of railway transportation the interest in monitoring systems is constantly increasing. These devices include sensors and electronic components, which need electric power supply for their proper working. However not all railway lines and vehicles are provided with electric power, furthermore, it can be complex to provide energy to sensors by cables in some location of the vehicle. The demand of a widespread distributed electrical energy can be fulfilled by energy harvesting techniques from primary sources. This paper analyses the different concepts of energy harvesters proposed in literature for the railway field, both for on board and wayside applications. The harvesters are classified according to the source from which energy is harvested and for each type of harvester advantages and disadvantages are critically discussed. The proposed review highlights the most promising solutions regarding energy harvesting in order to support future researches concerning this topic.

Study of the use of microwave radiation for heating process fluids in a vehicle

The predominance of a cold climate in the territory of the Russian Federation causes the prevalence of low-temperature conditions during the operation of vehicles, which cause a decrease in the reliability of the engine start-up and an increase in its warm-up time. At the present time, changing the operating modes of the engine fuel system, the introduction of additives to improve the quality of fuel, as well as the use of various types of heaters, one of which is the heating of process fluids with microwave radiation are ways to solve these problems. The use of microwave radiation for heating liquids is considered in the field of railway and pipeline transport, but is not well understood in road transport. Earlier studies have allowed to establish the change in physic and chemical properties in the processing of fuel microwave radiation. The purpose of this article is to study the effect of the use of microwave-treated fuels on the quality of engine start-up and warm-up under low temperature conditions.

Development of train ride comfort prediction model for railway slab track system

Abstract Despite considerable importance of train ride comfort (TRC) in railway slab tracks, there is no TRC prediction model for the slab tracks in the available literature. In this regard, a practical TRC prediction model was developed in this research, taking into account all the track and rolling stock influencing parameters. For this purpose, a vehicle/slab-track interaction model was developed. The model was validated using the results obtained from a comprehensive field test. The effects of rail pad, resilient layer, subgrade, properties of rolling stock suspension systems and vehicle speed on the TRC were studied through a parametric study of the model in which random rail irregularities with various severities were considered. The results obtained were used to develop the TRC prediction model. The accuracy of the model predictions was evaluated by comparing them with those obtained from a railway field. It was shown that the TRC prediction model developed here is a reliable tool for estimation of the TRC from slab track properties, rolling stock parameters and track irregularities. Applicability of the model in the real world of practice is illustrated.

On the fatigue improvement of railways superstructure components due to cold expansion – Part I: Experimental analysis

The fatigue strength improvement of materials and structures has always been the subject of studies, as a consequence of the rapid development of technologies and strictive safety requirements. In the railway field the fatigue resistance problem is thoroughly studied due to high transportation safety standard. Fatigue cracking is a major issue, in particular at rail-end-bolt holes. Cold Expansion is a common technique to induce beneficial residual compressive stresses around the holes, with the aim to improve the fatigue life of the rail. This paper is the first of a two part-series dealing with the study of the residual stress-strain field induced by the cold expansion process around rail-end-bolt holes. In Part I of this series, a contribution to better understanding the whole strain field distribution arising around rail-end-bolt holes during and after cold expansion is presented. Strains were experimentally measured using both electrical strain gauges and 2D-Digital Image Correlation. Contrary to common literature, strain-time history during the entire cold expansion process was investigated, in order to capture the highly non-linear elasto-plastic response of the material; the results of this study has been used in Part II of this series for the validation of the finite element model described there. The cold expansion process was applied to three rail holes, having equal nominal diameter. At first, the experimental results concerning each expanded hole are analysed. Then, all the results are compared, in order to evaluate the repeatability: - of the measurements; - of the Cold Expansion process; - of the adopted experimental technique, and, above all, to extrapolate the distribution of the hoop and radial residual strains as a function of the distance from the hole edge. At the end, results obtained by strain gauges and 2D-Digital Image Correlation are compared: a good agreement is found on the central flat surface of the rail web, which guarantees the availability of a robust and valuable highly non-linear reference result that has been used for the validation of the finite element model presented in Part II of this series.

High Accuracy Positioning of Backbone Network Infrastructure and Mobile Objects

This article deals with the system of high accuracy positioning of backbone railway network infrastructure and mobile objects of the Republic of Kazakhstan. Using the developments of high accuracy satellite positioning systems and backbone geodetic networks for creating the system of high accuracy positioning in the railway field will allow determining coordinates of backbone network infrastructure and mobile objects and sites of defects revealed with high accuracy and, moreover, will possess the high degree of reliability of conducted measurements of railway infrastructure elements. High accuracy positioning can be provided by the implementation of reference GNSS stations along the backbone railways. The relevance of the study is that the project implementation will allow providing the high accuracy monitoring of defects and/or deviations of the rail track elements from design parameters, movement speed increase and railway transportation safety increase.

Non-Destructive Characterization of Railway Materials and Components with Infrared Thermography Technique.

Infrared (IR) thermography technology is one of the leading non-destructive evaluation (NDE) techniques based on infrared detection. Infrared thermography, in particular, has the advantage of not only being used in non-contact mode but also provides full images, real-time inspection, and relatively fast results. These advantages make it possible to perform thermal imaging analysis of railway materials and/or components, such as brake disc simulation, monitoring of abnormal heat generation, and monitoring of temperature changes, during mechanical tests. This study introduces the current state of research on railway materials and/or components using IR thermography technology. An attempt was made to characterize the deterioration of electrical equipment of diesel electric locomotives using infrared thermal imaging techniques. In addition, surface temperature monitoring was performed during tensile testing of railway steels using a high-speed infrared camera. Damage evolution due to the hot spot generation of railway brake discs was successfully monitored using high-speed IR cameras. In this paper, IR thermal imaging technology, used as a non-destructive evaluation analysis in the railway field, was introduced, and the results of recent research are presented.

Pengembangan Manajemen Sumber Daya Manusia Berbasis Kompetensi Guna Meningkatkan Kinerja Pegawai Dan Dosen Polikteknik Perkeretaapian Indonesia

Manajemen sumber daya manusia adalah salah satu ilmu dalam mengatur tenaga kerja (SDM) agar efektif dan efisien membantu terwujudnya tujuan dari suatu organisasi. Politeknik Perkeretaapian Indonesia sebagai salah satu lembaga pendidikan tinggi yang dibentuk untuk menyiapkan SDM yang unggul di bidang perkeretaapian. Politeknik Perkeretaapian Indonesia melakukan berbagai upaya dalam meningkatkan kualitas mutu pendidikan. Kompetisi penyiapan SDM yang semakin tajam tersebut memberikan implikasi pada organisasi institusi Politeknik Perkeretaapian Indonesia untuk melakukan perubahan yang berorientasi pada kualitas dengan memberikan motivasi kepada para pegawai dan dosen untuk lebih giat bekerja secara professional. Harapanya adalah pegawai akan lebih meningkatkan kinerja sesuai dengan standar yang telah ditentukan. Akan tetapi kenyataanya adalah model manajemen yang sudah ada sebelumnya belum mampu meningkatkan kinerja pegawai dan dosen. Hal tersebut terbukti bahwa berdasarkan data yang didapat dari Kasubag Kepegawaian pada bulan April 2019 bahwa dari 150 pegawai sekitar 25 pegawai yang bekerja tidak sesuai dengan bidang keahlihan yang dimiliki, sehingga memberikan pengaruh yang signifikan terhadap hasil kinerja pegawai. Disamping itu beberapa dosen kurang termotivasi untuk melakukan Tri Darma Perguruan Tinggi, seperti pengabdian masyarakat, dan penelitian. Dalam penelitian ini peneliti ingin mengembangkan model manajemen MSDM guna meningkatkan kinerja pegawai. Metode yang digunakan dalam penelitian ini adalah Research & Development (R&D). Hasil penelitian Model Manajemen MSDM berbasis kompetensi mampu meningkatkan kinerja dosen dan pegawai untuk lebih produktif.

Reproduction of Local Strong Wind Area Induced in the Downstream of Small-Scale Terrain by Computational Fluid Dynamic (CFD) Approach

In this research, the computational fluid dynamic (CFD) approach was applied for the solution of the problems of local strong wind areas in railway fields, and the mechanism of wind generation was discussed. The problem of local wind occurring on a railway line in winter was taken up in this research. A computational simulation for the prediction of wind conditions by large-eddy simulation (LES) was implemented, and it was clarified that local strong wind areas are mainly caused by separated flows originating from small-scale terrain positioned at its upstream (at approximately 180 m above sea level). Meanwhile, the effects of the size of the calculation area and spatial grid resolution on the result of calculation and the effect of atmospheric stability were also discussed. It was clarified that in order to simulate the air flow characteristic of the separated flow originating from the small-scale terrain (at an altitude of approximately 180 m) targeted in the present research, approximately 10 m of spatial resolution of computational cell in the horizontal direction is required. In addition, the effect of stable stratification on the flow was also examined. As a result, lee waves were excited at the downstream of the terrain over time in the case of stably stratified flow (Fr = 1.0). The reverse-flow region lying behind the terrain, which had been observed at a neutral time, was strongly inhibited. Consequently, a local strong wind area was generated at the downstream of the terrain, and a strong wind area passing through the observation mast was observed. By investigating the increasing rate of speed of the local strong wind area induced at the time of stable stratification, it was found that the wind was approximately 1.2 times stronger than what was generated at a neutral time.

Dynamic Analysis of Circular Plates in Contact with Fluid and Resting on Two-Parameter Foundations

The dynamic behaviour of a circular plate in contact with fluid and resting on two-parameter elastic foundations is of interest in the field of geotechnics, structure, highway, railway, oil and gas and mechanical engineering. In this work, the dynamic behaviour of circular plate in contact with fluid and resting on Winkler and Pasternak foundations is investigated. The coupled differential equation of the system is analysed using differential transformation method. Good agreements are established when the results of the analytical solutions are compared to the results of the experimental investigation as reported in literature. The analytical solutions obtained are used to investigate the effects of elastic foundation parameters on natural frequency, combine foundation parameters on natural frequency, plate in contact with fluid and that of radial and circumferential stress on mode shapes. From the results, it is observed that, increases in elastic foundation parameter increases the natural frequency in all cases. Presence of fluid reduces the natural frequency of the plate. Also, it is established that mode shapes are not altered by the presence of fluid. However, mode shape displacement occurs due to presence of radial and circumferential stresses. Since the study provides a physical insight into the vibration mode of the structure, it is expected that the study will enhance better understanding on the dynamic behaviour of a circular plate in contact with fluid and resting on two-parameters elastic foundation.

Photonics-assisted direction-of-arrival estimation of electromagnetic interference for GSM-R system in high-speed railways

In the field of high-speed railways (HSRs), electromagnetic interference (EMI) to the wireless train-ground communication system (e.g., the GSM-R system for train scheduling and dispatching) severely reduces the operational efficiency and even results in accidents. The direction-of-arrival (DoA) estimation of EMI is crucial for detection and removal. A photonics-assisted system is proposed to estimate the DoA of EMI for the GSM-R system along the HSRs in a remote and real-time mode. The proposed scheme is featured by simultaneous photonics-assisted detection and location (DoA estimation) of the EMI, with the advantages of strong EMI immunity, low loss transmission, and remote distribution. Here, an integrated optical multichannel transceiver operating as the photonic front end is used to acquire multiple delayed replicas of the electromagnetic signals, and then, a multiple signal classification algorithm is used to estimate their DoAs at the center station. In the indoor experiments, the DoAs ranging from −60 deg to +60 deg are successfully estimated with errors less than 1.2 deg in a 10-km radio-over-fiber link. In the field trials, the GSM-R signal accompanied by a suspected EMI is detected with DoA errors less than 1.8 deg.

Influence of wheel diameter difference on surface damage for heavy-haul locomotive wheels: Measurements and simulations

Fatigue damage of wheel surface is a common problem in railway field, leading to significant operational disturbances and maintenance costs due to frequent wheel turning. After wheel lathe turning, the initial wheel diameter difference (WDD) also accelerates the initiation and propagation of wheel surface cracks. Combined with a practical case in heavy-haul locomotives, the paper presents an investigation of the effects of initial WDD on wheel surface damage, including extensive field observations, statistical analysis of measured data, and numerical simulation of locomotive dynamics. By observing the crack characteristics, and measuring the wear and diameter of wheels, it is found that the large initial WDD caused by unqualified lathe turning is mainly responsible for the observed wheel damage. From the statistics of 53 heavy-haul locomotives in the depot, large WDD commonly exists even in the new turned wheelsets (more than 4 mm). Cracks and partial wear are both developed quickly on the wheelsets with large initial WDD, and always occurred on the wheels with smaller diameter, whereas the other side wheels are in good condition. Moreover, the wheel surface cracks are mainly located on a band of 65–120 mm from the wheel flange back. In addition, the numerical simulations show that the initial large WDD first causes the wheel partial wear, and further exacerbate the initiation of surface cracks.

An innovative model for the prediction of wheel - Rail wear and rolling contact fatigue

One of the issues in the railway field is the damage caused by wear and RCF which deeply affects wheel and rail. These phenomena are closely connected and directly impact both on vehicle dynamics (comfort, stability, safety, etc.) and on the costs (line management, maintenance, etc.), decreasing the useful life of wheel and rail. To face these problems and detect abnormal operating conditions, this work aims at developing a modelling approach for railway and tramway applications that effectively combines wear and RCF models. The former has been validated by means of on-field experimental data whereas the latter through specific laboratory tests carried out on a dedicated test-rig. The proposed approach is capable of simultaneously predicting both the profiles shape evolution due to wear and the total RCF damage along the wheel and rail profiles, reaching a good compromise between accuracy and efficiency. Thanks to the high numerical efficiency, the wear-RCF model can be easily implemented into complex multibody models of railway and tramway vehicles to perform large-scale simulations.

Prediction of IGBT power module remaining lifetime using the aging state approach

Insulated Gate Bipolar Transistor (IGBT) is the core power device in the fields of railways, new energy sources, and automobiles. The safe and reliable operation of IGBT is the basis to ensure the sustained and steady development of all walks of life. The junction-to-case thermal resistance of the IGBT power modules can manifest the fatigue degree of the solder layer. The saturation voltage drop manifests the aging degree of the IGBT bonding wire. Therefore, the IGBT reliability can be judged by a certain rule along with the external parameters such as the junction-to-case thermal resistance Rth and the saturation voltage drop Vce. In order to grasp this rule, this study illustrates the correlations between the external parameters of IGBT and the number of power cycles. As a result, the functional relationships between the average change rate of junction-to-case thermal resistance and the number of power cycles (ΔR¯th—n) as well as the average saturation voltage drop rate of change and the number of power cycles (ΔV¯ce—n) have been gained from IGBT test samples. After obtaining these functional relationships, for any IGBT of the same model in working condition, a proposition of judging the aging degree can be obtained. Here, the aging degree of the IGBT is represented by a real number in the interval [0, 1] and the reliability of the above proposition is calculated from the standard deviation of the working lifetime of each test sample. The method proposed in this study can not only be used to judge the aging degree of IGBT, but also to estimate the remaining lifetime.

Development and validation of wear models by using innovative three-dimensional laser scanners

One of the main problems in railway and tramway systems, both dynamically (safety, comfort etc.) and economically (planning of maintenance interventions, reduction of wheel and rail lifetime etc.), is represented by the wear of wheel and rail profiles, due to the wheel–rail interaction. The profile’s shape variation caused by wear influences the dynamic behaviour of the vehicle and, in particular, the wheel–rail contact conditions. Hence, nowadays, one of the most important topics in the railway field is the development of reliable wear models to predict profiles evolution, together with the use of more efficient and accurate measuring instruments for the model validation and the rolling components inspection. In this context, the aim of this research work is the development and the validation of wear models, using experimental data acquired through an innovative measuring instrument based on noncontact three-dimensional laser scanning technology. The tramway line of the city of Florence, characterized by very narrow curves and critical in terms of wear, has been chosen as a reference test case. Moreover, the inspection procedures currently adopted on this line for the maintenance plan are based only on classical two-dimensional contact measurement systems, not so accurate for a complete wear assessment. Therefore, the introduction of a new three-dimensional laser scanning technology may have a great impact on the maintenance management of the line.

LAWANG SEWU’S MONUMENTALITY ARCHITECTURE

Abstract- Lawang Sewu is a historic cultural heritage building that became one of the leading tourist attractions in Semarang City. The building that was built in 1904 and completed in 1918 has experienced some changes in function and ownership. Lawang Sewu was originally the administrative office of Nederlands-Indische Spoorweg Maatschappij (NIS). NIS is a private company engaged in the field of railways. Lawang Sewu also witnessed the 5 days battle in Semarang that occurred on 14 to19 August 1949. It was marked by the location of Tugu Muda Monument located on the west side of Lawang Sewu. Apart from the historical side, spatial relationships between Lawang Sewu and Tugu Muda Monument in the area, making the building of the former NIS office is significant. Architecturally, the significance can be explained in the context of the monumentality of the building.The Monumentality of Lawang Sewu is explained gradually from several aspects. First, an architectural object can be monumental seen from the link between architecture and monument. Second, the historical and cultural dynamics attached to the building. Third, the building relationship with the surrounding environment and its architectural character. Referring to the concept of architectural monumentality enclosed by Yoshinobu Ashihara and Louis Kahn, monumentality is described based on the image of the singularity of buildings that arise from its relationship with the surrounding environment and the quality of the atmosphere of space formed from building elements.As an architectural object, Lawang Sewu has the required value in the definition of monuments and monumental properties. These values include aspects of history, technology, architecture, and culture. Not only has monumental values, Lawang Sewu also experienced the dynamics of changing the meaning of monuments as described in the Nine Points on Monumentality. In addition, Lawang Sewu is a building inherent in the collective memory of society. This is evidenced from the name Lawang Sewu which is actually a nickname. In the architectural context, Lawang Sewu is able to show the monumental value of its unique impression on Tugu Muda Monument Area. Then, both the architectural elements and the structures seen in the atmosphere of space in Lawang Sewu able to convey the image of a certain period. Elements of buildings with economic value and high technological updates also form the value of Lawang Sewu monumentality. Key Words: significance, monumentality, history, culture, Lawang Sewu, railway

Mechanical properties of a novel dactyl-inspired green-composite sandwich structures with basalt fiber

The laminated structural dactyl club of mantis shrimp consisting of the impact and periodic region has been studied, but most researchers only focus on the excellent impact resistance and strength of periodic region through the thickness direction. In this paper, a novel dactyl-inspired basalt fiber-reinforced sandwich-structural composite (BFSC) was manufactured based on two regions of the dactyl club by compression molding process. The BFSC was compared with discontinuous basalt fiber-reinforced composite (DBFC) in mechanical tests of tensile, flexural, compression, hardness and impact. As a result, the strength of tensile, compression, flexural and impact of BFSC were 104 MPa, 112 MPa, 135 MPa and 116 MPa, respectively, which increased to 65.4%, 9.8%, 11.6% and 30.3% than that of DBFC (63.3 MPa, 102 MPa, 121 MPa and 89 MPa). The modulus of tensile and compression of BFSC were 3740 MPa and 971 MPa, respectively, which increased to 58.3% and 38.7% compared with that of DBFC (2362 MPa and 700 MPa). The excellent mechanical properties of BFSC can be attributed to the damage of special sandwich structure, which has failure mechanisms at the microscopic scale, including the crack of resin matrix, fiber breakage, fiber/matrix debonding and delamination. This work presents a novel dactyl-inspired green-composite sandwich structures with basalt fiber. As a lightweight material, it has a wide application in the field of aerospace, high-speed railways and automotive.

A Comprehensive Method of Apportioning Reliability Goals for New Product of Hydraulic Excavator

It is important to allocate a reliability goal for the hydraulic excavator in the early design stage of the new system. There are some effective methods for setting reliability target and allocating its constituent subsystems in the field of aerospace, electric, vehicles, railways, or chemical system, but until now there is no effective method for the hydraulic excavator or engineering machinery. In this paper, an approach is proposed which combines with the conventional reliability allocation methods for setting reliability goals and allocating the subsystem and parts useful in the early design stage of the hydraulic excavator newly developed. It includes Weibull analysis method, modified Aeronautical Radio Inc. (ARINC) method, and modified systematic failure mode and effect analysis (FMEA) method. After completing reliability allocation, it is necessary to organize the designers and experts to evaluate the rationality of the reliability target through FEMA analysis considering feasibility of the improvement technically for the part which was new developed or had fault in its predecessor. The proposed approach provides an easy methodology for allocate a practical reliability goal for the hydraulic excavator capturing the real life behavior of the product. It proposes a simple and unique way to capture the improvement of the subsystems or components of the hydraulic excavator. The proposed approach could be extended to consider other construction machinery equipment and have practicality value to research excellent mechanical product.

Modeling Process of a Third Dimension Universe for Transportation Simulation: Application to Railway System

In past years, 3D models of virtual worlds have been used in several applications such as urban planning, simulation and design. In the railway field, that we chose as a field of application to illustrate our proposals in this article, simulation makes sense because of the complexity involved and the risk for personnel during upstream phases of validation. To be able to simulation with enough precision, the model of the virtual universe is a key point. Especially For train component simulation, an accurate and detailed model of the train component is mandatory. For training the drivers within a serious game, a high visual quality is required. Obtaining a single model supporting these two constraints at the same time at the lowest cost is still an open issue and involved many actors. Our contribution is a methodology and a process for creating a virtual universe model, based on automatic model generation, in order to allow the creation of large-scale universes while guaranteeing a level of details appropriate to the need, a model of constant quality and including semantic data necessary for simulation, while reducing the modeling costs and the modeling duration. The proposed process is applied to train simulation.

High-Accuracy Calibration of On-Site Multi-Vision Sensors Based on Flexible and Optimal 3D Field

Global calibration of multi-vision sensors in the railway fields is easily affected by on-site complex environments, such as lighting and self-occlusion, which makes it difficult for existing methods to achieve high-accuracy calibration. In this paper, a high-accuracy and flexible calibration method of multi-vision sensors in the outdoor railway fields based on flexible and optimal 3D data field through the combination of articular arm and metal target embedded with luminescent LEDs is proposed. Firstly, a high-accuracy and flexible 3D data field with multiple angles and views is constructed by the articular arm and the metal target rapidly; Secondly, the high-frequency multi-exposure imaging mode and multi-scale image feature points extraction are adopted, and the high-accuracy reposition is achieved through Kalman filter, which can reduce the impact of image noise efficiently; Finally, the RANSAC method is utilized to optimize the 3D data field, forming the optimal 3D data field, and the optimal target chains corresponding to each group of cameras are established. The maximum likelihood solution of global parameters is solved by nonlinear optimization. Simulation experiments verify the feasibility of the proposed method. Meanwhile, physical experiment results show this method can reduce the outdoor environment impact and improve the calibration and measurement precision effectively. In addition, the computational efficiency of the proposed method is about 11.2 times than multi-images averaging method, the calibration and measurement accuracy improve about 20 and 2.9 times respectively, which is suitable for the high-accuracy and flexible global calibration in the complex railway environment.