GROUND VIBRATION GENERATED BY A HARMONIC LOAD ACTING ON A RAILWAY TRACK

✍ Scribed by X. SHENG; C.J.C. JONES; M. PETYT

• Publisher: Elsevier Science
• Year: 1999
• Tongue: English
• Weight: 531 KB
• Volume: 225
• Category: Article
• ISSN: 0022-460X
• DOI: 10.1006/jsvi.1999.2232

✦ Synopsis

A calculation method has been produced for the propagation of vibration in the ground from a stationary oscillating load applied via a railway track structure. The model includes the track as an in"nite layered beam structure resting on a ground made up of in"nite parallel homogeneous elastic layers. These layers may either be constrained at the lower interface or coupled to an elastic half-space. A similar model, based on wave propagating "nite elements, has previously been shown to be useful in predicting the behaviour of real soils and railway tracks, but the applicability of that model was limited by long computation times. The present method is more e$cient in calculating the responses at a large number of positions. The development of the theory allows analysis in terms of the amplitudes of di!erent wave types propagating along, and normal to, the track. Example calculations are presented for a ground consisting of a layer on a half-space. By changing only the depth of the layer, two di!erent wave propagation regimes are found, the "rst where propagation takes place via modes of the layer and the second, where propagation takes place via the bulk waves in the layer and the Rayleigh wave in the substratum. Both examples show the track structure to have a strong e!ect on the directivity and amplitude of the response of the ground surface.