Deep basement constructions are always anticipated in densely populated and urban areas withrnlimited construction spaces like Addis Ababa. The design of basement retaining walls and theirrnsupporting system involves careful analysis, design and monitoring due to the sensitivity of groundrnmovements that can cause damage to the adjacent buildings, roads and other utilities. Therefore,rnanalyses and parametric study are important to better understand the response of the soil tornexcavation and to predict the magnitude and pattern of ground movement. rnIn Addis Ababa the most common type of retaining wall for deep excavation is contiguous boredrnpile wall. This retaining method may not be relatively effective in terms of various parameters likernsoil type of the area, embedment depth, size of the wall, and construction cost. Thus otherrnalternative retaining systems should be considered and analyzed to select a best option. There arernpapers written to analyze the performance of different types of retaining structures. The resultsrnpresented in those papers are for a specific type of retaining structure and lack cost estimation.rnThese two factors limit the flexibility to compare results in an organized manner and havernreasonable up-to-date information about the construction cost. Therefore, it is necessary torncompare soil retaining structures used for deep excavations by including additional comparisonrnfactor, which is cost of construction. rnThe objective of this thesis is to identify the effect and performance of diaphragm, contiguous andrntangent bored pile retaining walls for basement work in terms of bending moment, shear force,rnlateral wall deflections and ground movements by varying wall types, varying size of the wall andrnvarying wall embedment length during stages excavation using the software package PLAXIS 2Drnversion 8.2 for the chosen case study. Besides that, to determine the appropriate wall type forrnbasement based on economical aspect. Results of these analyses were recorded in terms horizontalrndisplacement of the wall, ground settlement behind the wall, shear force and bending momentsrninduced in the wall due to an adjacent deep excavation. And those Results from software analysisrnwill be compared with each other to select the best option which is worth to consider based onrntheir performance. And also they will be compared based on the cost which the walls worthâ€™s.