ABSTRACT: In urban environment, excavation adjacent to existing buildings is common. Supporting excavation is important to
prevent damaging of the adjacent buildings. There are many factors affecting the selection of the supporting system. Some of them are
soil behavior, type of foundation, foundation level of the adjacent buildings, and the budget of the project under construction. In order
to reduce the surrounding soil movement due to deep excavation, a three dimensional Finite Element (3D FE) study was carried out in
this paper, considering soil-structure interaction. A piled supporting system was selected because it is common and relatively
economic to use in cohesive soil in Egypt. A parametric study was performed to study the effect of the stiffness of the supporting
system on minimizing the ground deformation. From the results, some recommendations are given in terms of excavation depth, soilpile
stiffness, and pile embedded depth.