Abstract

Nonlinear Elastic Rayleigh Wave Scattered by Local Surface Inhomogeneity

Yu.M.Zaslavsky (Institute of Applied Physics Russian Academy of Sciences, Nizhny Novgorod, Russia)

e-mail: zaslav@hydro.appl.sci-nnov.ru

The solution of the problem of elastic Rayleigh wave scattering by local surface inhomogeneity is presented. The inhomogeneity is simulated by a thin disk that slightly rises above the plane surface. There is slow acoustical nonlinearity in the material of the disk consisting in small different bulk and shear elastic moduli in the first and third quadrants which gives a break of the stress-strain caracteristic. This bimodular characteristic is probably typical of the contact area of local inhomogeneities immersed in the ground. The average value of bulk and shear elastic disk moduli is the same as in the medium of the half-space. Calculation results permit to compair the scattered wave level at the fundamental and second harmonic frequencies. The reception of the scattered R-wave at the fundamental and second harmonic frequencies may be concidered as some approach for increasing the localization precision within seismic vibration probing, exploration and surveying of the ground subsurface inhomogeneities.

Section : 6