Numerical simulation of the SASW test

doi:10.1016/0267-7261(92)90036-D

Soil Dynamics and Earthquake Engineering

Volume 11, Issue 4, 1992, Pages 213-227

https://doi.org/10.1016/0267-7261(92)90036-D Get rights and content

Abstract

The paper describes numerical simulation of the SASW test. Influences of the test setup and applied filtering criteria on the accuracy of the obtained field dispersion curve for various soil stratification conditions have been examined. The results presented indicate significant variations in the evaluated dispersion in cases of irregular soil profiles if the existing criteria are applied. A new filtering criteria has been proposed.

References (14)

N. Gucunski
Generation of low frequency Rayleigh waves for the Spectral-Analysis-of-Surface-Waves Method
N. Gucunski et al.
Use of Rayleigh modes in interpretation of SASW test
N. Gucunski et al.
Inversion of Rayleigh Wave Dispersion Curve for SASW Test
N. Gucunski et al.
Instrumentation for SASW testing
J.S. Heisey et al.
Determination of in situ shear wave velocities from Spectral Analysis of Surface Waves
D.R. Hiltunen
Experimental evaluation of variables affecting the testing of pavements by the Spectral-Analysis-of-Surface-Waves method
E. Kausel
An Explicit Solution for the Green Functions for Dynamic Loads in Layered Media

There are more references available in the full text version of this article.

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An important constraint with geophysical testing methods based on the propagation of surface waves (active surface wave testing methods) comes from the filtering criteria that are used to avoid near and far-field effects. Such criteria suggest the use of a large receiver spread length to calculate accurate dispersion curves. However, for geotechnical investigations, the use of such a wide array is at best not desirable due mainly to site constraints and to the nature of the soil profile whose dynamic properties tend to vary laterally. The effectiveness of using smaller arrays of receivers covering limited distances to calculate accurate Rayleigh-waves dispersion curves and shear-wave velocity profiles is investigated. The methods used to compute the phase velocities are based on both group and phase velocity estimates. It is shown that the proposed method reduces the effects of body waves and the possibility of mode misidentification in the near and far-fields even when a limited number of traces covering relatively small distances are used. Also, the properties of the signal processing technique used to calculate the dispersion curves are shown to have a significant impact on the near and far-field effects. Numerical and experimental data are used to show the potential benefits of using shorter arrays of receivers to characterize the properties of different soil profiles with laterally varying properties.
Determination of allowable bearing capacity of shallow foundation using modified hyperbolic stress-strain model
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Numerical simulation of the SASW test

Abstract

Generation of low frequency Rayleigh waves for the Spectral-Analysis-of-Surface-Waves Method

Use of Rayleigh modes in interpretation of SASW test

Inversion of Rayleigh Wave Dispersion Curve for SASW Test

Instrumentation for SASW testing

Determination of in situ shear wave velocities from Spectral Analysis of Surface Waves

Experimental evaluation of variables affecting the testing of pavements by the Spectral-Analysis-of-Surface-Waves method

An Explicit Solution for the Green Functions for Dynamic Loads in Layered Media