Numerical and experimental comparison between two-station and multistation methods for spectral analysis



The popularity of surface wave methods in shallow geophysics and geotechnical engineering is increasing because of their cost effectiveness in testing hard to sample soils. The soil stiffness profile is obtained with an inversion process starting from the dispersive behaviour of Rayleigh waves. Typically the experimental dispersion curve is evaluated using a two-station procedure based on measuring the phase difference between impulsive signals recorded at two receivers (SASW test). In this paper a comparison between the results obtained with such approach and those relative to a multistation procedure based on frequency-wavenumber analysis is presented. The multistation approach introduces important improvements, reducing the testing time and the noise effects.

Both synthetic signals and experimental data have been used for a large spectrum comparison, whose main objective is to establish the differences in the experimental dispersion curves obtained with the two approaches.

Finally the stiffness profiles evaluated from the inversion of the multistation dispersion curve are compared to the results of seismic borehole methods.

    T …

Numero di pagine: 11

Articolo completo: