electromagnetic properties railway ballast research

(PDF) Reliability and operating properties of the ...

The analysis of the obtained results allows to The systems' mutual coexistence as well as their develop a research model of the electronic safety proper functioning within the railway area in the system, and to carry out a further reliability- particular electromagnetic environment, and operational analysis, taking into account operation ...

Benchmarking large scale GPR experiments on railway ballast

The overall aim of this project was to relate ground penetrating radar (GPR) to a ballast fouling index (FI). Laboratory research aimed at characterising the electromagnetic properties has enabled researchers worldwide to determine ballast thickness using impulse ground penetrating radar (GPR) – based upon derived values of the relative electrical permittivity or dielectric constant.

An investigation into the railway ballast dielectric ...

Non-destructive assessment of the electromagnetic properties of railway ballast aggregates. • Use of different GPR antennas and frequency systems within a unique experimental (laboratory) setup. • Identify critical factors as well as antennas and central frequencies most suitable for the investigation of railway ballast.

Electromagnetic properties of railway ballast | Request PDF

Request PDF | Electromagnetic properties of railway ballast | Laboratory experiments were undertaken to identify and characterise the dielectric properties of railway track ballast using Ground ...

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However, inferring mechanical properties from dielectric properties are seldom targeted for the combined use of these two nondestructive techniques. The specific objective of this paper is to determine the possible relationship of FWD pavement deflections and GPR data based on road test field surveys.

Railway ballast condition assessment using ground ...

This paper reports on the ground-penetrating radar (GPR)-based assessment of railway ballast which was progressively "polluted" with a fine-grained silty soil material. It is known how the proper operation of a ballast track bed may be undermined by the presence of fine-grained material which can fill progressively the voids between the ballast aggregates and affect the original strength ...

Automatic Classification of Ground-Penetrating-Radar ...

Fig. 3. Three traces from the railway data set. From top to bottom, they are from 50% clay ballast, clean ballast, and 50% coal ballast, respectively. (a) Time-domain waveforms. (b) Frequency magnitude spectra. delivers it to the transmitting antenna T x, which radiates an electromagnetic wave. Once the electromagnetic wave hits an

Bibliography of FRA Office of Research and Development ...

42 anthology of rail dynami~s research. 96 assessment of locomotive crew in-cab occupational noise exposure. 13 ballast and subgrade requirements study: railroad track substructure - design and performance practices. 13 ballast and subgrade requirements study: railroad track

Electromagnetic properties of railway ballast - ScienceDirect

1. To investigate whether the condition of the railway ballast can be classified by the dielectric constant, εr, — or the velocity of propagation of electromagnetic waves. 2. The suitability of the 500 or the 900 MHz GPR antennas in providing adequate penetration and of producing clear images of acceptable resolution. 3.

Open Foundation-

Study on Dynamic Mechanical Properties of High-Speed Railway Ballast Cement and Mechanism of Ballast Cement. 11. Elkin Ferney Rodrigu. Federal University of Rio de Janeiro. Research on Multifunctional and High-Precision Test Bench for HTS Maglev System and Magnetic Bearing. 12. Frank N. Werfel. Adelwitz Technologiezentrum

Electromagnetic properties of railway ballast — University ...

TY - GEN. T1 - Electromagnetic properties of railway ballast. AU - Clark, M. R. AU - Gillespie, R. AU - Kemp, T. AU - McCann, D. M. AU - Forde, M. C.

Simulation and Experiments on Signals of Ground ...

In order to simulate a real-life scenario within the context of railway structures, a total of four different ballast/pollutant mixes were introduced from ballast (clean) to highly-fouled (24 %).

Surface wave testing for characterization of ballast and ...

Monitoring and identifying the changes in mechanical properties of ballast and foundation soil in a track system are essential to schedule and predict maintenance costs and to improve safety. Unlike qualitative measurements with the electromagnetic waves, for example, Ground Penetrating Radar, wave velocity measurements provide an opportunity ...

A Computer-Aided Model for the Simulation of Railway ...

The synthetic samples of ballast are then visualized in the Computer-Aided Design CAD environment. The outcomes of the simulation are analyzed by comparison with the results of an experimental investigation carried out using a methacrylate container in which real …

Remote Sensing | Free Full-Text | Railway Ballast ...

Effective maintenance of railways requires a comprehensive assessment of the actual condition of the construction materials involved. In this regard, Ground-Penetrating Radar (GPR) stands as a viable alternative to the invasive and time-consuming traditional techniques for the inspection of these infrastructures. This work reports the experimental activities carried out on a test-site area ...

Railway Ballast: Insights from Discrete Element Analysis

processes Article Impact of Ballast Fouling on the Mechanical Properties of Railway Ballast: Insights from Discrete Element Analysis Luyu Wang 1, Mohamed Meguid 1 and Hani S. Mitri 2,* Citation: Wang, L.; Meguid, M.; Mitri, H.S. Impact of Ballast Fouling

Article Railway ballast monitoring by GPR: a test site ...

Tre University, on a railway stretch located within a depot area managed by the Italian National Railways (RFI) S.p.A. 2.1 Inspected material In order to reproduce different rates of fragmentation, two samples of typical limestone railway ballast were selected for the arrangement of the test site. Specifically, an ex-quarry ballast sample

Simulation and Experiments on Signals of Ground ...

The relation among curing ages, moisture content, compaction of soil cement and electromagnetic features was analyzed. The model of layered soil cement was established to simulate ground-penetrating radar (GPR) electromagnetic waves in the soil cement. The variation rules of dielectric constant and amplitude of radar signals were obtained.

Evaluating the Influence of Breakdown Fouling and Moisture ...

A complete study was performed to develop correlations between electromagnetic and mechanical properties of ballast. These correla tions can be used to predict the deformation properties of ballast and also its dynamic behavior under heavy axle load in …

(PDF) Research on proximity effect of electromagnetic railgun

PDF | The rails of electromagnetic railgun can be ablated by the temperature rise due to current concentration. The current distributions on the rails... | Find, read and cite all the research you ...

Railway track transmission line model: calculation of rail ...

equivalent rectangular ballast layer; as far as the equivalent rail is concerned, its radius is given by: req = Lr π (7) Being Lr the length of the rail foot (i.e. the part in contact with the sleeper). Formula (7) guarantees that the contact area between the equivalent semi-cylindrical rail and the sleeper is identical to the one of Fig. 1a.

Guideline on Methods to Find Hot-Spots on Rail Networks D1

research and innovation program under grant agreement No 636285 ... These features include ballast fouling, anomalies in railway embankments (including burrows), boundaries between layers, substructure condition, the water content of the soil ... Typical electromagnetic properties of some materials,

Railway Track Condition Assessment at Network Level by ...

Railway Track Condition Assessment at Network ... of GPR to assess the ballast condition is a challenging task because the material electromagnetic properties are sensitive to both the ballast grading and water content. This work presents a novel ... some GPR studies with a particular research interest to assess ballast fouling and moisture ...

Effects of natural abrasion on railroad ballast strength ...

1.Introduction. Railway ballast is primarily responsible for draining water away from the track. However, it also plays very important roles in resisting loading forces, reducing stress on the subgrade by distributing load, maintaining track geometry, and providing large voids for the storage and movement of fouling material, .Fouling is the introduction of finer particles less than 3/8 inch ...

Edinburgh Research Explorer

Railway, track bed, maintenance, GPR, ballast, testing, spent, analysis, benchmarking ABSTRACT The overall aim of this project was to relate Ground Penetrating Radar (GPR) to a ballast fouling index (FI). Laboratory research aimed at characterising the electromagnetic properties has enabled

(PDF) Model Track Studies by Ground Penetrating Radar (GPR ...

Laboratory experiments were undertaken to identify and characterise the dielectric properties of railway track ballast using Ground Penetrating Radar …

Preventive Maintenance of Railway ... - Railway Research

maximum depth of investigation. When the wavefront encounters a change in the electromagnetic properties of the medium due to, for example an interface between two different media (ballast – sub-ballast interface), part of the energy is reflected back to the …

Railroad Ballast Evaluation Using Ground-Penetrating Radar ...

The early detection of ballast fouling is of utmost importance to the safety of the rail system and its life-cycle cost-effectiveness. Ground-penetrating radar (GPR), a nondestructive evaluation tool, has shown its potential as a means of assessing the condition of the railroad substructure rapidly, effectively, and continuously.

A Review of Methods for Estimating Ballast Degradation ...

This paper presents a review of how ballast degradation, characterized by the accumulation of fines and increased moisture retention, affects the EM properties critical for GPR and contrasts the current methods used to estimate ballast conditions from GPR measurements. ground-penetrating radar, ballast degradation, nondestructive testing, railways.

[PDF] ASSESSMENT OF RAILWAY TRACK SUBSTRUCTURE …

Ground penetrating radar (GPR) has been employed to assess railway track substructure (ballast, subballast, and subgrade) conditions. GPR involves transmitting radar pulses into the substructure and measuring return signals that have reflected off boundaries between substructure layers with different electromagnetic properties. The principle electromagnetic property of the layers is the ...

1 2 properties 3 - UWL Repository

5 1 the subballast layers) as well as in routine maintenance operations (e.g., the monitoring of the segregation 2 processes of the ballast aggregates) in railway engineering. 3 4 5 Figure 1. Typical ballasted rail track substructure and corresponding A-scan from a GPR measurement. 6 7 2. Objectives and methodology This paper focuses on8 the assessment of "critical" geometric features of ...