الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
Limit state design (LSD) has already been the basic design method for the design of reinforced concrete structures as introduced in the Egyptian code of practice for the
design and construction of reinforced concrete structures (ECP-203, 2007) and for steel building design code. However, the current issue for the Egyptian’s geotechnical design
code is still based on the traditional global factor of safety (GFS) design approach. A
harmonization between the design codes essentially required, so the eotechnical engineering professions in Egypt are in the process of evaluating the LSD to be incorporated in the new geotechnical Egyptian code. The main benefit of introducing
LSD in the new geotechnical Egyptian code is to it provides a consistent design approach between structural and geotechnical engineers, it is more precise calibration and more sophisticated because the partial factors are applied directly to the parameter that are the source of variability in the strength.
The difference of all geotechnical design philosophies is how to attain an acceptable level of safety or reliability. Working stress design (WSD) also referred to as allowable
stress design (ASD) or GSF design method has been used, as a basic design approach, for many years in civil engineering. It was recommended for the geotechnical
applications in Egypt in the ’80s as adopted in the first Egyptian code of practice for the design of foundations. In the GFS design a single factor of safety (FS) is used to represent the safety margin. LSD, which can be approached by two methods. The first method is the European method which relies on specified partial factors applied directly to the geotechnical strength parameters of cohesion and angle of internal friction, and also applied partial factors to loads as variable or permanent loads. The second method
is the North American method (LRFD) also known as a factored resistance methodology is represented by an overall specified resistance factor is applied to the assessed ultimate
geotechnical resistance and partial factors applied to loads.
After providing the two design method the design and construction of mechanically stabilized earth (MSE) walls were discussed. MSE Walls are a composite construction material in which the strength of the engineering fill is reinforced by the use of strong
tensile reinforcement in the form of metal strips, geogrids or geotextiles and a facing element which is vertical near vertical. MSE Walls are utilized all over the word, but their uses are uncommon in Egypt, so it necessary to do more studies on this structure
for understanding the behavior of MSE walls. Then the three design approaches of Eurocode 7 were proposed to be applied in the new suggestion proposed Egyptian code with a fitting method for the external stability of
MSE walls. By fitting technique the values of partial safety factors of the LSD were checked out to give the same design estimates obtained from WSD method. The new suggestion proposed Egyptian code evaluating by calibration of partial safety
factors in Eurocode for external stability of MSE walls, which is the main point of my study.
Finally, two examples are solved by using Eurocode 7, the suggestion proposed
Egyptian code and the current Egyptian code with manually and equilibrium method. Key words: working stress design (WSD) method, limit state design (LSD), Eurocode 7, mechanically stabilized earth (MSE) walls, calibration, limit equilibrium analysis.