الفهرس 
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Abstract
The issue of movements of insitu walls has become more important over the past
decades with.new technologies being introduced, and increased concern about litigation
over possible damages to adjacent facilities.
This research presents information about the construction of subway stations using
the cut - and - cover techniques employing reinforced concrete diaphragm walls constructed
in the ground by means of a process of trenching with the aid of a fluid support (bentonite).
This study intends to update and clarify previously available data for controlling ground
movements with minor effects on the adjacent existing structures.
The analysis of the diaphragm wall is conducted through two domains:
First In the early stage, the bentonite suspension has the ability to form a membrane of
low permeability at the soil - liquid interface, allows development of the fuU hydrostatic
pressure of the fluid against the sides of the trench,
Second The braced wall is a powerful, specific soil - structure interaction problem of
embeded reinforced concrete wall on deformable soil media
This research proposes a numerical modelling for analysis of diaphragm walls during
the different construction stages. Several analyses have been made to improve undestanding
of the conditions and mechanisms governing the stability of slurry - filled trenches. The
associated variations in the surrounding soil stress field and deformations during wall
construction and subway excavation are investigated, the progress of construction
portrayed
The numerical techniques, such as the finite element method are quite useful to carry
out such analysis. A computer program was upgraded using the Fortran language. Eight-
node isoparametric finite elements were used to simulate the soil continuum and the
diaphragm wall, the nonlinear stress- strain behaviour of the soil employing modified
Duncan model (1984) utilized.
Spring type interface elements were introduced to model the soil - diaphragm wall contact
surface.
This thesis illustrates a comparative study between results of the nonlinear finite
element analysis and the field measurements which had been compiled during construction
of the Greater Cairo Underground Metro, Lines 1 and 2. Also, results of the analysis were compared with the predicted values from the commonly used empirical design rules of such
walls.
The study has concentrated exclusively on the numerical modelling of slurry trench
wall by simulating two operations as one stage and multi - stage:
I. The progressive excavation of relatively narrow trench in the ground and the slurry is
introduced simultaneously. On completion, the trench is filled with slurry.
2. The slurry is displaced from the bottom upwards by the continuity of the supply of
concrete. Finally. the trench is filled with concrete.