TY - GEN
T1 - Wave dispersion in granular soil by DEM analysis in two and three dimensions
AU - Thomas, C. N.
AU - Mylonakis, G.
AU - Papargyri-Beskoy, S.
PY - 2010
Y1 - 2010
N2 - Numerical studies are conducted to investigate the existence of wave dispersion in resonant column tests on dry granular soil. The distinct element method (DEM) in the time domain is employed in two and three-dimensions to simulate the laboratory apparatus. The investigations focus on the effect of sample width, voids ratio. viscous damping and wavelength, on propagation velocities of longitudinal harmonic waves in rectangular samples consisting of uniform grains. It is shown that granular materials may exhibit anomalous dispersion that is, wave velocities that increase with increasing excitation frequency. This increase may be significant for squatty samples, yet becomes less pronounced for slender samples. The dispersion effects tend to be more pronounced in 2D over 3D analyses which suggests waveguide dispersion. Similar findings have been reported in some experiments on granular materials, but have not been systematically explored by numerical means. Results are presented in the form of dimensionless graphs and charts that elucidate the salient features of the problem.
AB - Numerical studies are conducted to investigate the existence of wave dispersion in resonant column tests on dry granular soil. The distinct element method (DEM) in the time domain is employed in two and three-dimensions to simulate the laboratory apparatus. The investigations focus on the effect of sample width, voids ratio. viscous damping and wavelength, on propagation velocities of longitudinal harmonic waves in rectangular samples consisting of uniform grains. It is shown that granular materials may exhibit anomalous dispersion that is, wave velocities that increase with increasing excitation frequency. This increase may be significant for squatty samples, yet becomes less pronounced for slender samples. The dispersion effects tend to be more pronounced in 2D over 3D analyses which suggests waveguide dispersion. Similar findings have been reported in some experiments on granular materials, but have not been systematically explored by numerical means. Results are presented in the form of dimensionless graphs and charts that elucidate the salient features of the problem.
KW - Distinct element method
KW - Numerical analyses
KW - Wave dispersion
UR - http://www.scopus.com/inward/record.url?scp=84903839763&partnerID=8YFLogxK
U2 - 10.1142/9789814322034_0023
DO - 10.1142/9789814322034_0023
M3 - Conference contribution
AN - SCOPUS:84903839763
SN - 9814322024
SN - 9789814322027
T3 - Proceedings of the 9th International Workshop on Mathematical Methods in Scattering Theory and Biomedical Engineering: Advanced Topics in Scattering and Biomedical Engineering
SP - 218
EP - 225
BT - Proceedings of the 9th International Workshop on Mathematical Methods in Scattering Theory and Biomedical Engineering
PB - World Scientific Publishing Co. Pte Ltd
T2 - 2009 9th International Workshop on Mathematical Methods in Scattering Theory and Biomedical Engineering
Y2 - 9 October 2009 through 11 October 2009
ER -