الفهرس 
CHAPTER (1) INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
Problematic soft clay soil is widespread all over the world and it is characterized by its low bearing capacity, low shear strength, high compressibility, and high-volume instability. East Port Said Region is considered one of the most important industrial regions in Egypt that characterized by its deep layers of soft clay. In this research, deep mixing method (DMM) with ordinary Portland cement or quicklime has been utilized for soil improvement. Laboratory trial mix samples were prepared to evaluate the effects of binder type, binder content, water-cement ratio, and sample age on unconfined compression strength and permeability. The results showed that cement is effective in improving soft clay, but quicklime is not effective in improving such soils. An increase of binder content, and/or sample age increased unconfined compression strength and reduced permeability. Three small scale physical laboratory models were applied to verify finite element analysis (PLAXIS 2D. and PLAXIS 3D.). Then, a parametric study was carried out to show the effect of binder content, improvement depth, and replacement ratio on consolidation settlement and time. The numerical results showed that consolidation settlement reduced with increasing binder content, improvement depth, and replacement ratio. Improved soil had lower consolidation time than unimproved soil even though deep mixed piles had lower permeability than untreated soil. An empirical equation was obtained from the research results to calculate the final settlement using DMM. Finally, the integrated obtained results of finite element and the laboratory trial mix samples recommended improving Port-Said soft clay by using deep mixing and shallow mixing, where they have a positive effect on reducing consolidation settlement, time.
The Dissertation Organization
This introductory chapter highlights the purpose and scope of this research, while Chapter 2 describes some methods of soil improvement such as soil replacement, Pre-Compression, Preloading, vertical drains, dynamic compaction, mass stabilization, and deep mixing method. The most common methods are described and illustrated by examples. Then, methods of deep mixing, patterns, the strength of treatment area, settlement analyses, factors affecting deep mixing strength, quality control, quality assurance, benefits, and application are explained in detail.
Chapter 3 presents the laboratory testing on Port-Said Clay. First, the geotechnical properties of Port-Said Clay were explained due to the tests performed by the Suez Canal Authority Research Center. Second, soil mixing samples were mixed and treated with various binders, binder contents, and sample ages. The samples were prepared, stored, and the unconfined compression test was carried out as the main benchmark test to determine the efficiency of deep mixing method in improving the strength of soft clay soil. Thirdly three physical models were performed using simulated field and using the finite-element method (FEM) in the plane strain case. These methods were then compared together to verify the finite element method in deep mixing method.
Chapter 4 presents the use of plane strain numerical analysis for soft clay foundations to predict the consolidation settlement and time under different conditions such as, with and without deep mixing columns, various binder contents, pile depths, pile spacing, pile diameters, pile behavior systems, soil compression indexes, and with and without shallow mixing. Comparisons between these conditions are illustrated.
Chapter 6 includes the summary, conclusion, recommendation, and suggestions for future studies.