In recent years, It may be become able to meet the construction demand because of the uncontrolled increasing population at the big cities and city centers. The construction industry is directed to high rise buildings, multi story basements, subway and tunnels, due to this increasing demand. Civil engineers are required to keep in balance the ground on during the deep excavations, since the soil often have not keep itself. Soil must be supperted in order to ensure safety at the site of the excavation. For this reason, there are many methods are used and soil nailing system is one of them. Among the types of retaining structure, soil nailed walls prevent due to their advantages such as being economic, shorter application periods and ability to work in restricted areas. Therefore applications are increasing rapidly.In this study, a diaphragm wall with soil nails is modelled on a steep slope, and the effects of the number of different soil nails, different loads and soil types on the diaphragm wall are examined. Soil nail reinforced system is modelled with finite element method (FEM) by using Plaxis 8.2. In this study to ensure stability of the sand soil with different relative densities (Dr=%35 and Dr=%65), a diaphragm wall supported by soil nails is analysied numerically. The total, horizontal and vertical displacements of the diaphragm wall are obtained. The computed factor of safety values are found with PLAXIS 8.2 analysis program and are compared results of analysis. Total, vertical, and horizontal displacements for Dr=%65 soil were smaller than Dr=%35 soil but factors of safety were higher. Consequently; optimum result was obtained at Dr=%65 relative density and 6 soil nail case.
Key Words: Soil nail, Slope stability, Finite element method, PLAXIS.