الفهرس 
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Abstract
The basic premise of this work is the dynamic soil-structure interaction (DSSI)
between an underground structure and the supporting soil, which has a significant effect
on the response of the structure and the resulting localization of stresses and settlements
during seismic events. This thesis focuses on simulating the static and dynamic analysis
of diaphragm walls embedded through soil media. The Automatic Dynamic Incremental
Nonlinear Analysis (ADINA) software is used to model the structure and the surrounding
soil.
The soil surrounding the structure is modeled as Mohr-coulomb material whereas
the diaphragms walls, raft foundation, and the multi-storey building component are
modeled as an elastic material simulating the reinforced concrete. Many parameters are
considered including different types of soil, such as; medium stiff clay and dense sand
soil. Other structural parameters like the diaphragm width, embedment depth, and raft
foundation thickness. The presence of ground anchors system support is also considered
in the study. The loading pattern is divided into four phases; first stage is concerned with
static or consolidation phase in which the soil is allowed to consolidate under its own
weight. The second stage is includes modeling the diaphragm wall construction, ground
anchor construction, excavation, then constructing the raft foundation, followed by the
multi-storey building. The third stage is the main stage, in which the dynamic analysis is
performed by applying the seismic event. The final stage is another static phase in which
the pore water pressures generated during the dynamic analysis are allowed to dissipate,
and the settlements and stresses within the soil domain are also computed. The Northridge
earthquake record which occurred in San Fernando Valley with a Richter Magnitude of
6.7 is used in the dynamic analysis.
It was found that under static loading pattern, changes in diaphragm walls widths or
increasing the embedment depth of the diaphragm walls through the soil media in case of
clay soil could not achieve stability for the diaphragm walls, necessitating the use of
ground anchors system to achieve stability. On the other hand, when the diaphragm walls
constructed in sand soil media theoretical analysis showed stability of the diaphragm
under normal loading conditions, but practically ground anchors should be used to
account for any unexpected loads that may act during construction. Under the earthquake
event, the pore water pressure is increased suddenly while the effective vertical stress
decreases. This phenomenon is more pronounced in sand soil than the clay soil media.
High stresses took place in the soil under the diaphragm walls, behind the ground
anchors, and under the raft foundation.