الفهرس 
IntroductionOnly 14 pages are availabe for public view
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Abstract
In urban areas where space and property are a major constraint when constructing a
deep excavation, the use of a stable and effective retaining system is essential. The
choice of the retaining system depends on the site condition, the expected earth
pressure and the existence of water. Diaphragm walls are commonly used as a
retaining system that can withstand high values of earth pressure and also have good
performance with water existence.
The design output of retaining system depends mainly on soil parameters, site
conditions and adapted design approach. There are two design approaches for
solving geotechnical problems: working stress design approach (WSD) and limit
state design approach (LSD). WSD uses a global safety factor for all uncertainties
associated with geotechnical design. LSD accounts for uncertainties by applying
partial safety factors for different variables that affects the design output. Most
international standards use LSD approach for example EN1997, AASHTO and
BS8002. In contrast the Egyptian code of practice ECP 202 adapts WSD approach
as designing structural element uses ultimate design method so the straining actions
on the wall analyzed by ECP 202 are then multiplied by a factor of safety for design.
This study aims to emphasize the influence of adapting different design approaches
on design output results for a strutted diaphragm wall. Three different methods were
applied in this research: Analytical analys, numerical analysis and probabilistic
analysis. The analytical analysis was carried by using geo5 to estimate embedment
depth and straining actions on the retaining system. The numerical analysis was
carried out by using PLAXIS 2D. The probabilistic analysis was performed by
applying a simple MATLAB code.
In this thesis three different cases for strutted diaphragm wall were considered for
analytical and numerical analysis. The first case with a single strut and excavation
height 7m. The second case with two levels of struts with the same excavation height
as the first. The third case is for a 16m deep excavation with 5 levels of struts.
Implementing different safety factors applied by design standards. ECP 202 which
applies a global safety factor to increase passive resistance by increasing embedment
depth with 40%. EN1997 which applies partial safety factors for surcharge loading
and soil parameters with a set of different combinations. and AASHTO which
applies load and resistance factored design method (LRFD).