Seismic surface wave methods allow to retrieve the shallow subsurface shear wave velocity. Among these, the "Multi-channel Analysis of Surface Waves" is to date one of the most widely adopted non-invasive active-source approaches in the professional world for the evaluation of the stiffness properties of the ground for geotechnical engineering purposes. The method utilizes the dispersive nature of surface waves by constructing the dispersion curve which is then inverted to obtain the shear wave velocity profile. Dispersion curves generation typically requires the transformation of the recorded seismograms into the frequency-velocity (f-V) domain. Commercially available inversion algorithms assume the subsurface model as a stack ofhomogeneous parallel layers, but unfortunately this may lead to misleading results if the actual soil profile is far from the assumed ID geometry. We investigate the effects oflateral heterogeneities due to variations oflayer thicknesses on the f-V spectrum to assess the limitations of the ID approach and thus tojudge the reliability of such surface waves interpretation.
Thickness variations in layered subsurface models-Effects on simulated MASW
Bignardi S.
;
2014-01-01
Abstract
Seismic surface wave methods allow to retrieve the shallow subsurface shear wave velocity. Among these, the "Multi-channel Analysis of Surface Waves" is to date one of the most widely adopted non-invasive active-source approaches in the professional world for the evaluation of the stiffness properties of the ground for geotechnical engineering purposes. The method utilizes the dispersive nature of surface waves by constructing the dispersion curve which is then inverted to obtain the shear wave velocity profile. Dispersion curves generation typically requires the transformation of the recorded seismograms into the frequency-velocity (f-V) domain. Commercially available inversion algorithms assume the subsurface model as a stack ofhomogeneous parallel layers, but unfortunately this may lead to misleading results if the actual soil profile is far from the assumed ID geometry. We investigate the effects oflateral heterogeneities due to variations oflayer thicknesses on the f-V spectrum to assess the limitations of the ID approach and thus tojudge the reliability of such surface waves interpretation.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
