Three-dimensional numerical analysis of slopes considering effects of surcharge loads

One of the problems that civil engineers frequently encounter in various construction projects is slope collapse problems. The factor of safety (Fs) of a slope depends on the geometry of the slope, soil parameters and many parameters related to surcharge loads. The (Fs) values required for slopes are generally lower than the values required for the stability of foundations. For this reason, slope failures are more common than wholesale collapses observed in other geotechnical structures. In cases where the surcharge loading is close to the top of the slope, 2D analyzes may not be sufficient to examine the failure mechanism, and in this case, 3D analysis may be necessary. These analyzes are often carried out with limit equilibrium methods (LEM), but with the development of technology, the use of finite element method (FEM) is also becoming widespread. FEM analysis can be advantageous in that it also gives values of deformations in slopes. However, these two methods use completely different approaches to calculating (Fs) values, and so the results are rarely exactly the same. In this study, the short-term stability of clayey slopes under surcharge loads was investigated using 2D LEM, 2D FEM, 3D LEM and 3D FEM. In 3D analyses, the effects of overcharge size and overcharge shape on the short-term stability of clayey slopes were investigated for various slope geometries and undrained shear strength values. This study reveals the differences in the analysis results using LEM and FEM.