Paper published in a book (Scientific congresses, symposiums and conference proceedings)
Decomposition of measured ground vibrations into basic soil waves
Macijauskas, Darius; Van Baars, Stefan
2013 • In Pietruszczak, Stan; Pande, Gyan (Eds.) Proceedings of the 3rd International Symposium on Computational Geomechanics (ComGeo III), Krakow, Poland, 21-23 August, 2013
[en] Man-made vibrations from different types of sources are usually measured on the surface of the ground or building. The measured signal is always the superposition of all travelling basic waves. For a homogeneous half space there are three basic waves – the Compressional (P-wave), Shear (S-wave) and Rayleigh wave (R-wave). Depending on the measuring equipment, only the accelerations or velocities in time of the superposed wave can be measured, but not the distribution of the individual basic waves.
Additional problems are that each of the basic waves has its own velocity, besides the body and surface waves have different attenuation laws. By using the rules of superposition of harmonic waves and also the propagation laws of the P-, S- and R-waves, it should be theoretically possible to split the measured superposed signal into the basic waves, because mathematically a system of equations can be assembled which describes the displacements at multiple measuring points in time.
In this paper this problem has been solved for a homogenous, elastic and isotropic soil, which is disturbed by a harmonically oscillating disc on the surface. A numerical simulation was performed using a finite element method. The displacements in time were recorded in 10 points on the surface and a system of superposed equations was assembled and solved.
The findings prove that each of the three basic waves has its own phase shift with the source, something which was not known before.
Disciplines :
Civil engineering
Author, co-author :
Macijauskas, Darius ; University of Luxembourg > Faculty of Science, Technology and Communication (FSTC) > Engineering Research Unit
Van Baars, Stefan ; University of Luxembourg > Faculty of Science, Technology and Communication (FSTC) > Engineering Research Unit
External co-authors :
no
Language :
English
Title :
Decomposition of measured ground vibrations into basic soil waves
Publication date :
21 August 2013
Event name :
The 3rd International Symposium on Computational Geomechanics (ComGeo III)
Event place :
Krakow, Poland
Event date :
from 21-08-2013 to 23-08-2013
Audience :
International
Main work title :
Proceedings of the 3rd International Symposium on Computational Geomechanics (ComGeo III), Krakow, Poland, 21-23 August, 2013
Editor :
Pietruszczak, Stan
Pande, Gyan
Publisher :
International Centre for Computational Engineering, Rhodes, Greece
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