52107
2021
eng
21
36
1
22
article
Zhejiang University Press
Hangzhou
Zhejiang University
1
--
--
--
Dynamic track-soil interaction – calculations and measurements about slab and ballast tracks
The dynamic behaviour of slab and ballast tracks has been investigated by measurements and calculations. Hammer impacts and train passages have been analysed. Measurements have been performed by geophones (velocity transducers) which have been time-integrated to displacements. The calculations are done in frequency-wavenumber domain for multi-beam-on-continuous soil models. The characteristics of the different tracks and track elements have been established in theory and experiment. The frequency-dependent compliances (displacement transfer functions) show clear rail-on-rail-pad resonances or highly damped track-soil resonances. Compared to the rail and sleeper, the track plate has much lower amplitudes. The slab track has usually the highest rail amplitudes due to soft rail pads. The train passage yields track displacements which are a superposition of the axle loads from the two neighbouring axles of a bogie and from the two bogies of two neighbouring carriages. This global behaviour is characteristic for the track plate of the slab track whereas the rails of the slab and the ballast track behave more local with only one bogie of influence. The measurements agree very well with the theory of the continuous soil in case of the six measured slab tracks and acceptably well for the six measured ballast tracks. The measurements allow to find appropriate model parameters and to check the models, for example the Winkler model of the soil has been found less appropriate as it reacts more locally.
Journal of Zhejiang University-Science A
1673-565X
10.1631/jzus.A1900651
publish
11.02.22021
false
true
Lutz Auersch
Samir Said
eng
uncontrolled
Slab track
eng
uncontrolled
Ballast track
eng
uncontrolled
Train passage
eng
uncontrolled
Hammer impact
eng
uncontrolled
Track-soil interaction
Ingenieurbau
7 Bauwerkssicherheit
7.2 Ingenieurbau
Infrastruktur
Datei im Netzwerk der BAM verfügbar ("Closed Access")
Graue Literatur
51257
2020
eng
21
49
20
2
article
Saxe-Coburg Publications
London
0
--
--
--
Vehicle-Track-Soil Interaction of Isolated, Un-isolated and Damaged Railway Tracks
This article deals with two topics of vehicle-track-soil interaction, the mitigation of railway induced ground vibration by soft track elements, and the identification of track damage. Theoretical results have been achieved by a combined finite-element boundary-element method (FEBEM). The theoretical results are confronted with measurements at four sites. Improved mitigation effects have been found for soft rail pads under heavy sleepers. The insertion loss, however, can be too optimistic if a strong vehicle track resonance occurs for the un-isolated reference track. Two measurement sites show this strong vehicle-track resonance at about 80 Hz, which has been approximated by using the results of a wide parameter study including the rail pad, ballast, and soil stiffness, as well as the ballast model and the soil layering. – The detection of slab track damage is mainly based on the differences of the receptance or compliance functions. Theoretical results have been confirmed by measurements at one site where a loss of contact between track plate and base layer was visible. Measurements at a second site with a hidden damage have been compared with the theoretical results of a loose sleeper. The differences between intact (or repaired) and damaged tracks are strong enough to encourage the further development of this method for the identification of track damages.
International Journal of Railway Technology
10.4203/ijrt.6.3.2
2049-5358
Lutz Auersch
eng
uncontrolled
Railway track
eng
uncontrolled
Track-soil interaction
eng
uncontrolled
Ground vibration
eng
uncontrolled
Mitigation
eng
uncontrolled
Under-sleeper pads
eng
uncontrolled
Track damage monitoring
Ingenieurbau
7 Bauwerkssicherheit
7.2 Ingenieurbau
Infrastruktur
Verlagsliteratur
Datei im Netzwerk der BAM verfügbar ("Closed Access")
42581
2017
eng
1
14
September
12
article
Elsevier
London
0
--
--
--
Track-soil dynamics – calculation and measurement of damaged and repaired slab tracks
The damage detection and repair control have become important tasks for ballast and slab tracks. Measurements which compare the damaged and the repaired status of the same track section at different times, or which compare a damaged and an intact track section at the same time, have been successfully performed at some sites in Germany. The loss of contact between the sleeper and the track plate, between the track plate and the base plate, and between the base plate and the base layer have been analysed. The soil properties of each site have been measured and have been used to establish realistic track-soil models. Theoretical results of the wavenumber domain and the finite-element boundary element method have been compared with the experimental results. The observed experimental and theoretical results, changes in the time histories of displacements and velocities due to train passages and in the transfer functions (receptances) due to hammer impacts, are encouraging that these measurements can be used to detect track damage.
Transportation Geotechnics
10.1016/j.trgeo.2017.06.003
2214-3912
Lutz Auersch
Samir Said
eng
uncontrolled
Railway track
eng
uncontrolled
Slab track
eng
uncontrolled
Track-soil interaction
eng
uncontrolled
Field tests
eng
uncontrolled
Track damage
eng
uncontrolled
Monitoring
eng
uncontrolled
Finite element method
eng
uncontrolled
Boundary element method
Ingenieurbau
Verlagsliteratur
Datei im Netzwerk der BAM verfügbar ("Closed Access")
41022
2017
eng
1
18
ID 1959286
2017
article
Hindawi
Indien
1
--
--
--
Simultaneous measurements of the vehicle, track, and soil vibrations at a surface, bridge, and tunnel railway line
A complex measuring campaign has been performed including the simultaneous measurement of vehicle, track, and soil vibrations during train runs at 16, 25, 40, 63, 80, 100, 125, 140, 160 km/h, and impulse measurements of the passenger car, three track sections and the soil. A ballast track on the soil surface and on a concrete bridge have been investigated as well as a slab track in a tunnel. The evaluation and comparison of all these data shows a generally good agreement for all components if the strong low- and high-frequency cut-off characteristics of the layered and damped soil are incorporated. There is a strong causal correlation between the vehicle and the soil by the dynamic excitation forces and a weak relation between the track and the soil by the axle-sequence spectrum of the train. However, the similarity between the axle-impulse spectrum observed at the track and the spectra of the ground vibration lead to the special excitation component of “scattered axle impulses” which is pre-dominant at the far-field points of the soil.
Shock and Vibration
10.1155/2017/1959286
urn:nbn:de:kobv:b43-410224
17.07.2017
Creative Commons - Namensnennung
Lutz Auersch
eng
uncontrolled
Railway
eng
uncontrolled
Ground vibration
eng
uncontrolled
Vehicle-track interaction
eng
uncontrolled
Track-soil interaction
eng
uncontrolled
Measurements
Sanitär- und Kommunaltechnik; Umwelttechnik
Verlagsliteratur
Datei für die Öffentlichkeit verfügbar ("Open Access")
Wissenschaftliche Artikel der BAM
Bundesanstalt für Materialforschung und -prüfung (BAM)
https://opus4.kobv.de/opus4-bam/files/41022/ShockVib2017ID1959286.pdf
26860
2012
eng
923
933
8
138
article
Soc.
New York, NY, USA
American Society of Civil Engineers (ASCE)
1
--
--
--
Dynamic behavior of slab tracks on homogeneous and layered soils and the reduction of ground vibration by floating slab tracks
The dynamics of slab tracks and floating slab tracks are analyzed by multibeam models for the track and by integration in the wave-number domain for the soil, which is modeled as a layered half-space. Frequency-dependent compliances and force transfers are calculated for a great variety of track and soil parameters. The distribution of the load and the displacements along the track is investigated as well as the wave propagation perpendicular to the track and the ground vibration amplitudes. The floating slab track has a dominating plate-mat resonance and a strong high-frequency reduction. A track-soil resonance can also be recognized for an unisolated slab track in the case of layered soils. Generally, there is a strong damping of the track by the soil. The reduction effect of the slab mat is mainly owing to the elimination of this strong damping. The continuous soil yields slightly different rules for the displacements and force densities than those of a Winkler support. The total force transfer from the rail to the soil is the best criterion to judge the effectiveness of a floating slab track in reducing the ground vibration at some distance from the railway line. The total force transfer is easier to calculate than the double Fourier integrals of the ground vibration amplitudes, namely in the far field, and it has the best correlation with the reduction of the ground vibration.
Journal of engineering mechanics / ASCE
29644
10.1061/(ASCE)EM.1943-7889.0000407
0733-9399
1943-7889
31.10.2012
Lutz Auersch
eng
uncontrolled
Railway track
eng
uncontrolled
Slab track
eng
uncontrolled
Floating slab track
eng
uncontrolled
Track-soil interaction
eng
uncontrolled
Track vibration
eng
uncontrolled
Ground vibration
eng
uncontrolled
Force transfer
Verlagsliteratur
Datei im Netzwerk der BAM verfügbar ("Closed Access")
13723
2006
eng
169
183
2
220
article
Institution of Mechanical Engineers
London
1
--
--
--
Dynamic axle loads on tracks with and without ballast mats - numerical results of three-dimensional vehicle-track-soil models
Ballast mats are an efficient measure to reduce the vibrations near railway lines. The vehicle-track system gets a low eigenfrequency due to the insertion of an elastic ballast mat under the ballast. For frequencies higher than this low vehicle-track eigenfrequency, the forces, which are generating the vibration of the soil, are considerably reduced. In this contribution, a combined finite-element boundary-matrix method is used to calculate a number of completely three-dimensional track models with and without ballast mats. The influence of the important parameters such as the stiffness of the ballast mat, the unsprung vehicle mass, the mass of the track, and the stiffness of the subsoil is investigated. The numerical results are presented as the transfer functions of the total force that is acting on the soil and generating the vibration of the environment. The effectiveness of ballast mats is achieved by division of two of these force functions. The general tendencies for this insertion loss are discussed and a comparison with measurements is given. To come to an improved practical tool for the design of ballast-mat tracks, the finite-element method results are approximated by a simple two-dimensional model of which the solution is given explicitly.
Proceedings of the institution of mechanical engineers F
15475
10.1243/09544097F00105
0954-4097
Sonderstandort: Publica-Schrank
26.10.2006
Lutz Auersch
eng
uncontrolled
Railway track
eng
uncontrolled
Track dynamic
eng
uncontrolled
Ballast mat
eng
uncontrolled
Vibration isolation
eng
uncontrolled
Insertion loss
eng
uncontrolled
Finite-element method
eng
uncontrolled
Track-soil interaction
eng
uncontrolled
Vehicle-track interaction
Verlagsliteratur
Physisches Exemplar in der Bibliothek der BAM vorhanden ("Hardcopy Access")