Slope stability analysis of a silica sand slope model subjected to surcharge load

Natural disasters such as landslides are frequent occurrences around the world. The loss of countless lives and valuable property continues to occur despite many studies on the behaviour of slopes have been conducted. In this study, GeoStudio software which is a popular and powerful Limit Equilibrium Method analysis tool was employed. The study was carried out using soil properties of silica sand under surcharge load conduction, which reveals that the surcharge load is the potential influencing factors on soil slope instability. SLOPE/W modelling was utilized to analyzed slope stability using Mohr-coulomb criteria. The soil properties of silica sand such as saturated unit weight (Ysat), angle of internal friction (Ø) and soil cohesion (c) used in this study were determined in consolidated-drained triaxial tests. The result of FOS obtained from SLOPE/W modelling analysis is 0.969 with applied surcharge load of 6.4kN/m³. SLOPE/W result was then compared with results from another well-known geotechnical software using Finite Element Method (FEM), namely Plaxis 3D under the same loading conductions. The results from Plaxis 3D analysis showed a FOS of 9.931. The main difference in the analysis approach between LEM and FEM shows the difference between FOS values. Therefore, it is crucial to conduct a slope stability analysis to assure the stability and safety of the slope.