Finite element analysis and design method of geosynthetic-reinforced soil foundation subjected to normal fault movement

Abstract

This paper presents a series of finite element analyses to investigate the performance and reinforcing mechanism of geosynthetic-reinforced soil (GRS) foundations subjected to normal fault movement. Numerical and experimental results of unreinforced and reinforced foundations were first compared for model validation. Parametric studies were then conducted to evaluate the influence of soil and reinforcement parameters on the performance of reinforced foundations. The total height of the baseline reinforced foundation was 3 m in the prototype scale, and this foundation was subjected to fault movement of up to 1 m (S/H = 33%). The variables considered in the parametric studies included reinforcement length, stiffness, ultimate tensile strength, vertical spacing, foundation height, and soil–reinforcement interface property. The numerical results revealed that FE analysis satisfactorily predicted the deformation behavior of unreinforced and reinforced foundations subjected to normal fault movement. Two main reinforcing mechanisms identified in this study were tensioned membrane and shear rupture interception effects. Based on the numerical results, regression equations for predicting the maximum angular distortion and the mobilized reinforcement tensile strain induced by normal fault movement were established. Design methods were also developed for determining the reinforcement length (against significant pullout) and failure strain (against breakage).