Experimental evaluation of the efficiency of trenches for the mitigation of train-induced vibrations (original) (raw)

761. Study of wave barriers design for the mitigati on of railway ground vibrations

Journal of Vibroengineering, 2012

Nowadays, the consolidation of the rail in highly p opulated areas has become a reality. Foundations, buildings, high accuracy devi ces and people are susceptible to suffer from vibrations induced by passing trains. Therefore, mo dels for predicting ground vibrations are required in order to determine new mitigation measu res. Rectangular open or in-filled trenches are a suitable solution to be used near constructed railway lines. Their installation is fast, easy and economic since no intrusion in the track is nee ded. In this work, the influence of the trench design on its effectiveness is analyzed considering a train moving with subsonic speed. A finite element model of the track has been developed and validated with real data registered along the tram network in Alicante (Spain). The analysis is c arried out in the time domain considering the quasi-static movement of the vehicles. The results demonstrate that, in ascending order, the most relevant parameters in a trench are its w...

Reducing Railway Induced Ground-Borne Vibration by Using Trenches and Buried Soft Barriers

Notes on Numerical Fluid Mechanics and Multidisciplinary Design, 2015

To reduce railway induced low frequency vibration, two mitigation measuresopen trenches and buried soft wall barriers, have been studied in this paper by using coupled finite element-boundary element models. These models were developed at KU Leuven and ISVR, and have been cross-validated within the EU FP7 project RIVAS (Railway Induced Vibration Abatement Solutions). Variations in the width, depth, location of trench and properties of soft barrier material are considered under various soil conditions. Results show that in all ground conditions, the notional rectangular open trench performs better than the other constructions. The width of an open trench has little influence on its performance, whereas increasing the width of a filled trench reduces the stiffness of the material, improving the performance of the trench. Likewise, fill materials with lower Young's modulus give higher insertion losses.

Study of the barriers for the mitigation of railway vibrations

The reduction of environmental interference caused by the passage of railway convoys at high speed, in recent years, has become a key element for optimization and approval of the design alternatives. Therefore the need to develop models which analyze the effects of the vibrations induced on buildings close to rail lines appears primary, in order to define and classify possible improvement choices. In this paper we analyze the problem of the propagation of vibrations in the ground and focus the attention on the dampening effect of a barrier placed between source and receiver, in particular, we model the phenomenon through the finite element method considering the presence in the ground of one or several discontinuities. A parametric study to investigate the importance of the position, for example, of the discontinuity, introduced by the membrane is performed; then, different numerical simulations are analyzed by changing the position, the dimension and the materials of the barrier in order to optimize the FE model in terms of stress agents on the foundations and to study how the wave propagation and the soil-structure interaction are influenced by the membrane which can be seen as a damping barrier.

Mitigation of Railway Traffic Induced Vibrations: The Influence of Barriers in Elastic Half-Space

Advances in Acoustics and Vibration, 2009

In this paper, the problem of vibrations induced by trains and their propagation through the soil is studied. Particular attention is focused on the vibration induced by trains in motion and on the effects of such vibrations on the foundations of buildings in proximity of the tracks. The interaction between propagating waves induced by trains in motion and buildings foundations is a problem which does not admit a straightforward analytical solution; thus a solution is given by the use of a model based on the finite elements method. Firstly, we analyze the theoretical aspects of the problem by considering constant or harmonic loads moving along a straight railway track; then, we define a transfer function soil-railway and the response function of the entire system. The study aims to address the wave propagation in an elastic semi-space and the presence in the ground of a discontinuity element, such as a barrier of a given depth is considered. The efficiency variation of barriers is analyzed in function of the different materials used, and different numerical simulations are analyzed in order to study how the wave propagation and the track-soil interaction are influenced by the membrane, seen as damping barrier.

Amplification of Vibrations in High-Speed Railway Embankments by Passive Ground Vibration Barriers

International Journal of Geosynthetics and Ground Engineering, 2020

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Effect of Trench Barrier on Free Field Motion Due to the Train and Highspeed Train Passages

Proceedings of the 7th International Conference on Computational Methods in Structural Dynamics and Earthquake Engineering (COMPDYN 2015), 2019

Railway transport is one the most preferable way of commuting from/to urban centers. Although it has several advantages on other ways of transportation such as its cost effectiveness, energy efficiency, safety and least dependency to weather conditions, there is also a disadvantage by inducing discomfort vibration to the surrounding area especially in the urban centers. In this study, a trench barrier along the track line has been used in order to reduce the vibration induced by trains and high-speed trains. A series of field testing has been carried out. The vibration levels from the freight/passenger trains and high speed trains passages were measured in three directions up to the 40m from the track lines. The average Vs30 value was 200m/s and the speed of the high-speed train was 250km/h at the site. As a vibration mitigation measure an excavated trench barrier has been used along the track line. The vibration levels with and without trench barrier have been compared for the freight/passenger trains and high speed trains passages. The obtained records have been analyzed both in time and frequency domains. The results showed that the trench barrier effectively reduces the vibration level.

Reduction of train-induced building vibrations by using open and filled trenches

A numerical investigation on the effectiveness of open and in-filled trenches in reducing the building vibrations due to passing trains is presented. Particularly, a two-dimensional soil-structure system containing the cross-section of a railway embankment, the underlying soil, a trench barrier and a nearby six-storey building is considered. For the analysis, a time domain coupled boundary element-finite element algorithm is employed. Unlike most of the previous formulations, this model completely considers the soil-structure interaction effects and directly determines the effect of the wave barrier on the structural response. The effects of geometrical and material properties of the trench and its backfill material on the structural response are investigated. The results point out that using a trench barrier, a reduction level up to 80% of the building vibrations and internal forces can be achieved. Increasing the depth or the width of a trench may improve its reduction effect and a softer backfill material results in a better isolation effect.

Stiff Wave Barriers for the Mitigation of Railway Induced Vibrations

Notes on Numerical Fluid Mechanics and Multidisciplinary Design, 2015

This paper studies the efficiency of stiff wave barriers for the mitigation of railway induced vibrations. Coupled finite element-boundary element models developed at KU Leuven and ISVR are employed; these models have been cross-validated within the EU FP7 project RIVAS [1]. A first mitigation measure consists of a block of stiffened soil included in a halfspace that acts as a wave impeding barrier. The existence of a critical frequency from which this mitigation measure starts to be effective, as well as a critical angle delimiting the area where the vibration levels are reduced, is demonstrated. Next, a sheet piling wall is considered, accounting for the orthotropic behaviour of this wall. Calculations show that the reduction of vibration levels is entirely due to the relatively high axial stiffness and vertical bending stiffness, while the longitudinal bending stiffness is too low to affect the transmission of vibrations. Field tests are being carried out in Spain and Sweden to confirm the conclusions of these numerical computations.