| Summary: | 碩士 === 國立臺灣大學 === 應用力學研究所 === 82 === The dynamics of fluid-saturated porous media is a subject with
application in numerous branches of science and engineering,
inc- luding geophysics, seismology, civil and mechanical
engineering. Extending the work of Terzaghi for soil
consolidation, Biot formulatedthe governing equation for the
two phases(solid and fluid) based on the assumption that the
solid obeys the the laws of linear elasticity and the fluid
obeys Darcy's law. According to this theory, a dynamic
disturbance produces two longitudinal( dilatational) waves and
one transverse(shear) wave in the media. The mathematical
description of internal seismic sources has classically been
pursued along two different lines:first, in of a body force
applied to certain elements of the medium containing the
source; and second, by some discontinuity in displacement or
strain, The second approach can usefully be incorporated into
the first. The explicit expression for the elastic media is
derived by Burridge and Knopoff for the equivalent body force
due to displacement. In this thesis we are begin with the Biot'
s theory of poro-elasticity media and following the concepts
of body force equivalents for the elastic-media, to derive the
expression for the body force to be applied in the absence of
a dislocation, which produces radiation identical to that of
the dislocation. Since in porous media, the body force are
divided into solid part and fluid part, we find that for the
slip faults only the body force of solid part are presents, but
for the separated faults both of solid and fluid parts are
presents, and the relative equivalent body force of fluid part
is characterized as a "fluid volume injection". At the end, we
consideration of the radiation due to force couple, fundmental
solutions and some approximation are given.
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