文档介绍：The implementation and application of dynamic
finite element analysis to geotechnical problems
A thesis submitted to the University of London
for the degree of Doctor of Philosophy and for the Diploma of
the Imperial College of Science, Technology and Medicine
By
Stuart Hardy
Department of Civil and Environmental Engineering
Imperial College of Science, Technology and Medicine
London, SW7 2BU
March 2003
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This thesis is dedicated to the memory of Myo Min Thaung
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ABSTRACT
The thesis details the development work that was undertaken to make dynamic
analyses possible with the pre-existing static geotechnical finite element program
ICFEP (Imperial College Finite Element Program). The changes were then
validated against known closed form solutions.
The possibility of analysing dynamic problems opens up a massive potential for new
research topics. For this study two where chosen.
The first of these concerns the use of bender element tests to measure the stiffness
of soils at very small strains. Their use is the laboratory has grown over recent years
due mainly to their low cost and the ease by which they can be incorporated in
other existing laboratory equipment. Ambiguity still remains surrounding their use
and several researchers have tried to remove this ambiguity paring
experimental data with results obtained using dynamic finite element analyses. All
the data published so far in the literature assumes two dimensional plane strain
conditions, were as in reality the problem is a truly three dimensional one.
In this thesis two and three dimensional analyses are presented for an extensive
range of input frequencies. Both types of analyses suggest that there is a small error
involved in the one dimensional assumption of shear wave propagation through the
sample. A numerical study is also presented for continuously cycled bender element
tests which have recently been proposed to