Numerical Analysis of Geosynthetic-Rammed Aggregate Pier Supported Embankments

Abstract

This paper presents results from numerical study to investigate the interactions between rammed aggregate piers and geosynthetic reinforcement in pier-supported embankments. The investigation was conducted using a two-dimensional, plane-strain, finite element model. Linear elastic, perfectly plastic constitutive model parameters were assumed fir the rammed aggregate piers, the matrix soil stiffness ratios considered in the analyses, a range of center-to-center soakings between piers was included. The geosynthetic reinforcement was modeled as a tensile element with various tensile stiffness values. Results obtained from this study provide insight into: (1) the interaction between the pier elements and the geosynthetic reinforcement to reduce differential settlement; (2) range of stress concentration ratio; and (3) tensile forced developed in the geosynthetic reinforcement. It is concluded that the efficiency of using geosynthetic reinforcement is improved as both the geosynthetic modulus and the pier-soil stiffness ratio increase.