| The surface wave exploration is a recently developed shallow exploration methods. It is widely used in engineering exploration, geotechnical engineering, groundwork evaluating, and so on. It plays an important role in engineering geophysical method. Its reason is through dispersion curves can be directly layer explanation. This method is simple, economical and practical. Therefore, Understand the Rayleigh wave propagation mechanism, and accurately extract frequency dispersion curve is significant particularly important.This thesis expounds the basic theory and the Rayleigh wave propagation characteristics of vibration. Through the first-order speed-stress elastic wave equation with the finite difference method and staggered grids, realized the Rayleigh wave numerical simulation, got the wave field snapshots and wave theory records, and used the simple model to test its true. To extracting frequency dispersion curves, introduced and realized fulfill the three methods: f-k method,τ-p method and phase-shift method. The extraction rate of the frequency dispersion curves which extracted by traditional method is not isometric changes. This thesis modified the traditional method. It can directly extract frequency dispersion curves in the f-v spectrum, avoided jump phenomena of frequency dispersion curves extraction which extracted by f-k method andτ-p method.First, simulated a theory of surface wave record, second, used all sorts of methods on record extracting frequency dispersion curves with, then verified its correctness by theoretical frequency dispersion curves, finally compared and analyzed the frequency dispersion curves. Discoveredτ-p method and phase-shift method effect is good, more close to the theoretical results. These two kinds of methods should be the top-choice in practical application.Extracted the frequency dispersion curves of field data and pointed out in the thesis to more in-depth study of the content and direction.
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