2D ANALYSES OF GLOBAL STABILITY OF A GEOSYNTHETIC-REINFORCED MECHANICALLY STABILIZED EARTH RETAINING WALL WITH DIFFERENT SOIL CONDITIONS

Abstract

The technology of reinforcing slopes with geosynthetics retaining walls has been widely applied in highways, infrastructure, hydraulics, seaports and civil works. The stability of geosynthetic-reinforced retaining walls is the major interest. The limit equilibrium method (LEM) is regularly known as the primary method for stability analysis of unreinforced and reinforced slopes due to its economy, effectiveness and simplicity. The paper presents several limit-equilibrium methods for slope stability analysis. A case study is taken from the section from Km0+360 to Km0+440, which belongs to the Huong Son-Kep town highway project, with an embankment height of 9 meters. The soil foundation profile consists of an organic soil layer with a thickness of 0.3 to 0.5 m, followed by a layer of clayey soil in semi-hard to hard state. The soil parameters are taken from the in situ and laboratory tests. The stability of a 9-height geosynthetic MSE wall is analyzed by employing various LEMs embedded in Geostudio software version 2018 R2. The paper then evaluates the influence of different soil conditions, including the internal friction angle, cohesion, unit weight and surcharge on the stability of the wall. The numerical outcomes indicate that the Janbu method gives a factor of safety that is 8% smaller than that of Bishop, Spencer and Sarma. The Bishop method is then suggested for the following studies. Additionally, the results indicate that the parameters of the foundation soil truly impact the stability of the geosynthetic-reinforced retaining wall structure.