posted on 2017-07-14, 12:39authored byVictor V. Krylov
In the present paper, the effects of focusing of ground vibrations generated by high speed trains travelling at trans-Rayleigh speeds, i.e. under the condition of ground vibration boom, are considered theoretically. These effects are similar to the effects of focusing of sound waves radiated by supersonic aircraft. In particular, if a railway track has a bend, e.g. to provide the possibility of changing direction of train movement, the Rayleigh surface waves generated by high-speed trains under the condition of ground vibration boom may become focused. This results in concentration of their energy along a simple caustic line at one side of the track and in the corresponding increase in ground vibration amplitudes. The effect of focusing of Rayleigh waves may occur also if a train moves along a straight line with acceleration a and its current speed v(t) is higher than Rayleigh wave velocity in the ground. In the present paper, both the above-mentioned focusing mechanisms are investigated in detail using the Green's function formalism and the expressions for space-time distributions of track-train-induced dynamic forces that take into account either track curvature or train acceleration. It is shown that in both these cases the effect of focusing can result in noticeable increase in generated ground vibrations. The obtained results are illustrated by numerical calculations.
History
School
Aeronautical, Automotive, Chemical and Materials Engineering
Department
Aeronautical and Automotive Engineering
Published in
Soil Dynamics and Earthquake Engineering
Volume
100
Pages
389 - 395
Citation
KRYLOV, V.V., 2017. Focusing of ground vibrations generated by high-speed trains travelling at trans-Rayleigh speeds. Soil Dynamics and Earthquake Engineering, 100, pp. 389-395.
This work is made available according to the conditions of the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International (CC BY-NC-ND 4.0) licence. Full details of this licence are available at: https://creativecommons.org/licenses/by-nc-nd/4.0/
Acceptance date
2017-06-19
Publication date
2017-06-27
Notes
This paper was accepted for publication in the journal Soil Dynamics and Earthquake Engineering and the definitive published version is available at http://dx.doi.org/10.1016/j.soildyn.2017.06.015