Analysis of dispersion curves of Rayleigh waves in the frequency-wavenumber domain

摘要

The method of spectrum analysis of surface waves (SASW) is discussed briefly. The analysis of the dispersion curves of Rayleigh waves in the frequency-wavenumber (f-k) domain is suggested due to the problems encountered in SASW. Three models of the layered media are considered according to typical situations in practice. All the modes that can be effectively excited are analyzed. The excitation and propagation characteristics of the Rayleigh waves are investigated by numerical simulation. The effects of some parameters such as number of channels and distance (s) between the source and the first receiver on the dispersion curves are investigated in detail for three models. Some important results about the number of receiver channels, relative error, mode jumping, and other aspects are obtained. It is found that reliable dispersion curves can be obtained by f-k analyses when the distance between the first receiver and the source is greater than one half the wavelength (0.5lambda).