Saturated Ground Vibration Analysis Based on a Three-Dimensional Coupled Train-Track-Soil Interaction Model

Abstract

A novel three-dimensional (3D) coupled train-track-soil interaction model is developed based on the multi-body simulation (MBS) principle and finite element modeling (FEM) theory using LS-DYNA. The novel model is capable of determining the highspeed effects of trains on track and foundation. The soils in this model are treated as saturated media. The wheel-rail dynamic interactions under the track irregularity are developed based on the Hertz contact theory. This model was validated by comparing its numerical results with experimental results obtained from field measurements and a good agreement was established. The one-layered saturated soil model is firstly developed to investigate the vibration responses of pore water pressures, effective and total stresses, and displacements of soils under different train speeds and soil moduli. The multi-layered soils with and without piles are then developed to highlight the influences of multi-layered soils and piles on the ground vibration responses. The effects of water on the train-track dynamic interactions are also presented. The original insight from this study provides a new and better understanding into saturated ground vibration responses in high-speed railway systems using slab tracks in practice. This insight will help track engineers to inspect, maintain, and improve soil conditions effectively, resulting in a seamless railway operation.

Seismic metamaterial barriers for ground vibration mitigation in railways considering the train-track-soil dynamic interactions

“…The 3D coupled train-track-soil interaction model has been validated in previous studies, and the validation results can be found from [4] and [5].…”

“…Train-induced ground vibrations can negatively affect surrounding residents, buildings, tunnels, drainage systems, overhead wiring structures, and so on [4,5,34,35,36]. Effective and efficient vibration mitigation solutions are desperately needed for high speed rail networks.…”

“… is the spatial frequency of the roughness. The PSD function can be transformed into vertical roughness along the longitudinal distance of the track using a time-frequency transformation technique, as shown inFigure 3.The material properties of the CRH380 EMU Train and CRTS II slab track can be found from[4] and[5]. (a) Roughness with distance (b) PSD with wavelength The roughness of rail surface 3.2 Modeling of soils and seismic metamaterials Soils are composed of subgrade soils and ground soils.…”

Sustainability of Vibration Mitigation Methods Using Meta-Materials/Structures along Railway Corridors Exposed to Adverse Weather Conditions

“…Based on dynamic amplification factors, geological condition, and the mitigating locations, the attenuation methods can be classified into three categories, including: (i) mitigating vibrations at the source, (ii) attenuating vibration intensity in the propagation path, and (iii) isolating the receiver such as surrounding structures from vibrations [5,6]. Compared with the other two types of mitigation methods (i.e., methods (i) and (ii)), it is rather difficult and often cost-consuming to build a vibration isolation system or to change the foundation condition under the existing buildings or infrastructures [7][8][9][10]. Therefore, the vibration mitigations at the source or at the transmission path are preferable to be applied in practice.…”

Effect of Track Irregularities on the Response of Two-Way Railway Tracks

“…This assumption is not useful while considering track irregularities. Furthermore, a lot of FEM based parametric studies have been carried out to investigate the effect of moving load under different track and ground conditions [16][17][18][19][20][21][22].…”