MSc Thesis Title: Numerical study of dynamic vibrations impact on railway embankments
Thursday 25 October 2018, at:13:30, Venue: Hall Κ3.A17
Examination Committee
- Associate Professor Yiannis Tsompanakis (advisor)
- Assistant Professor Tryfon Daras
- Associate Professor Nikolaos Lagaros
Abstract:
The main aim of this thesis is to investigate the important and multidisciplinary issue of ground vibrations caused by high-speed trains. For this purpose, the existing international literature has been studied, followed by a detailed numerical investigation of the impact of the vibrations on the railway embankment.
Firstly, a general overview of the subject is presented, focusing on the basic concepts of railways as well as the theoretical aspects of elastic waves propagation. The mechanism of the generation of these vibrations and the parameters that influence their propagation are also described. Subsequently, the available methods for simulating this complex phenomenon are presented. Moreover, several existing models that are used to simulate train, railway infrastructure and ground are presented. Then, mitigation measures for limiting train vibrations are briefly outlined, with particular reference on the implementation of expanded polystyrene geofoam (EPS) as basic construction material of the rail embankment.
Finally, the numerical analyses, the results and the related discussion, as well as the derived conclusions and suggestions for further research are presented. Autocad 2017 software was used to design the three-dimensional model of the railway-embankment-ground system, while the finite element software ANSYS 17.0 has been for utilized for the numerical analyses. In the performed analyses, several key factors are investigated: the impact of the train speed, the usage of EPS and the supporting ground type (soil or rock). The maximum vertical displacements are examined as a rational measure of the induced vibrations magnitude.
