Physical Ultrasonic Modeling Of Rayleigh Wave Field In The Near Vicinity Of An Anisotropic Wave Barrier.

Since composite wave barriers were suggested by Biagi et al. (1990), Leung et al. (199(l), Its<br>and Lee (1993a) to increase the screening efficiency for protection of buildings from groundtransmitted<br>vibration, several theoretical and experimental studies were conducted to analyze<br>scattering of surface waves at various models of the barriers. In particular, 3D physical ultrasonic<br>experiments were carried out (Its, Anisimov, and Lee; 1998) to study Rayleigh wave<br>scattering at a narrow vertical anisotropic slab embedded between two isotropic blocks. These<br>experiments were designed to analyze the surface wave in the far-field zone. The experimental<br>scattering coefficients were compared with the theoretical results obtained by the Green’s<br>function method (Its and Lee; 1993b, 1994). In this paper we report the results of ultrasonic<br>experiments which were designed for the near-field zone. The same model of the anisotropic<br>barrier as in (Its, Anisimov, and Lee; 1998) was used, but the profiles were shot in a wavelength<br>vicinity as well as inside the slab.