Diffraction of SV Waves by Circular Canyons of Various Depths
Publication: Journal of Engineering Mechanics
Volume 115, Issue 9
Abstract
The scattering and diffraction of plane SV waves by circular cylindrical canyons of various depths in an elastic half space is studied in this paper. The canyons studied here range from shallow circular to semicircular canyons in an elastic half space. The series of Bessel function expansions is used to solve the problem. For incidence beyond critical angle, the surface waves generated are expanded in terms of finite Fourier series that also involve Bessel functions. The number of steps and operations involved in the calculations is small, and the method is applicable to a wide range of frequencies, thus making it preferable to the presently available numerical techniques. The surface displacement amplitudes and phases that are presented shows that the results depend on the following parameters: (1) The angle of incidence, (2) the ratio of canyon depth to its half width, h/a; (3) the dimensionless frequency of the incident SV wave, η; and (4) Poisson's ratio, ν. The presence of the canyon in the elastic half space results in significant deviation of both the displacement amplitudes and phases on nearby ground surface from that of uniform half space motions, especially at high frequencies.
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Information & Authors
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Published In
Journal of Engineering Mechanics
Volume 115 • Issue 9 • September 1989
Pages: 2035 - 2056
Copyright
Copyright © 1989 ASCE.
History
Published online: Sep 1, 1989
Published in print: Sep 1989
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