electromagnetic properties railway ballast research

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

7901 SAICE Journal of Civil Engineering Vol 55 No 3

ballast fouling, earthworks INTRODUCTION The aim of a railway substructure investiga-tion is to characterise the track substructure based on its geotechnical properties. Care should be taken when conducting a substructure investigation to establish the correct remedial action (Brough et al 2003). Traditionally, for a typical rail line investiga-

(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 Ballast Fouling Detection Using GPR Data ...

ABSTRACT Ground‐penetrating radar has been recently used for quantifying railway ballast fouling conditions. This paper discusses two approaches for processing the railway ballast ground‐penetrating radar signal: the discrete wavelet transform method and the short‐time Fourier transform method. Ground‐penetrating radar field data collected in Wyoming in 2007 by two 2‐GHz air ...

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 ...

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.

ASNT NDT Library - $name

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 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.

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 ...

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

IET Digital Library: Characterisation of ballast materials ...

In recent years the use of high frequency GPR antennas such as the 2GHz horn antenna have become popular for railway trackbed evaluation due to their ability to help determine the extent of fouling within the ballast layer. Fouling of the ballast affects both its strength and drainage properties. The theory is based on the scattering behaviour of GPR signals in an inhomogeneous media ...

Ted Sussmann | University of Hartford

My research is focused on sustainable transportation infrastructure including rail, highway, and pipeline. The target of this research is characterization of material properties and evaluation of the influence of the materials on safety, life-cycle cost, and maintenance requirements to help improve sustainability of infrastructure investments.In graduate school I focused on infrastructure ...

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 …

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 %).

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.

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 ...

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,

Research on Railroad Ballast Specification and Evaluation

Research on Railroad Ballast Specification and Evaluation GERALD P. RAYMOND ... rock, slag, and gravel railway ballast sources are summarized in this paper. Comments are included about the new Canadian Pacific Rail ballast specif i ... These two properties, texture and composition, are …

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.

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) Railroad Ballast Evaluation Using Ground-Penetrating ...

Academia.edu is a platform for academics to share research papers. (PDF) Railroad Ballast Evaluation Using Ground-Penetrating Radar Laboratory Investigation and Field Validation | Imad L . Al-Qadi - …

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.

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

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 ...

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 ...

[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 ...

NDT Techniques in Railway Structure Analysis

3.1 Railway Ballast Evaluation Ballast is made of crushed hard rock, of which the small-sized particles have been sieved away. The ballast of a railway line must perform many different functions some of which are (Clark et al. 2001): reduce stresses applied to weaker interfaces, resist vertical, lateral and longitudinal forces applied to