universidad nacional de c´ordoba - Facultad de Ciencias Exactas ...

ABSTRACT
This thesis presents a new formulation of the Indirect Boundary Element Method (IBEM)
based on the principle of virtual work for the dynamic analysis of frame structures buried in
semi-infinite elastic media. Unlike conventional IBEM formulations, the present one leads
to symmetric stiffness matrices for the continuum domain that may be defined in terms
of conventional structural analysis variables (i.e., generalized displacements and lumped
forces). It is shown that, in the context of the present formulation, rotation degrees of
freedom (DOF) may readily be introduced in the interpolation scheme with very little
additional computational effort. By means of the present formulation, a two-node element
with three DOF per node is defined for the analysis of plane frames buried on a half-space
subjected to in-plane loads and moments. In order to show the consistency of the present
formulation with well established results, the static and dynamic stiffness of a single piles
and pile groups, as evaluated by means of the present formulation, is compared with other
results from the literature. Finally, the dynamic stiffness of a single buried frame under
vertical and horizontal loading is studied. The analysis shows that the stiffness of the full
frame may not always be accurately estimated by means of results for single piles, even
though proper dynamic interaction factors devised by Gazetas et al. ([10]) are taken into
account.
Thesis supervisor: Dr. Carlos A. Prato
Title:
Plenary Professor
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