Stability Analysis Of Tiered Geosynthetic Reinforced Soilwall With Pre-Stressed Anchor Pile

For the height limit of single step geosynthetic reinforced soil wall, the tiered geosynthetic reinforced soil wall is widely used now. Existed researches show that lateral deformation and stress concentration occur at the bottom of tiered geosynthetic reinforced soil wall. To insure the stability, pre-stressed anchor cable pile has been set at the bottom of wall and form a composite retaining structure. This paper draw a conclusion that the global stability of tiered geosynthetic reinforced soil wall can be calculated according to soil slope by analyze related design methods as FHWA & NCMA. Based on principle analysis of traditional limit equilibrium method and shear strength reduction method by FEM, this paper separately uses five different traditional slice methods and shear strength reduction method performs the stability calculation of composite retaining structure. Conclusions as follow: two different types of stability analytical method all fit the demand of that composite retaining structure; calculated results of slice method similar to finite element method and has its own feature; pre-stressed anchor cable anti-slide pile can apparently develop the whole stability of tiered geosynthetic reinforced soil wall; the factor of safety calculated by Janbu simplified method is smallest at each working condition; differences exist in each slice method so should choice suitable one; with the filling height increase, the factor of safety of whole composite retaining structure decreased and loads of anti-slide pile increase. Conclusions can be referenced by similar project.